Some minor spelling fixes in wxPropertyGrid documentation

Also fix a couple of things in the actual header for consistency with
the same fixes done in the documentation.

No real changes.

interface/wx/propgrid/manager.h

@@ -355,7 +355,7 @@ public:
     int GetPageByName( const wxString& name ) const;
 
     /**
-        Returns index for a relevant propertygrid state.
+        Returns index for a relevant property grid state.
         If no match is found, wxNOT_FOUND is returned.
     */
     int GetPageByState( const wxPropertyGridPageState* pstate ) const;

interface/wx/propgrid/propgrid.h

@@ -433,8 +433,8 @@ enum class wxPGKeyboardAction
 
     Call wxPropertyGrid::SetSortFunction() to set it.
 
-    Sort function should return a value greater than 0 if position of p1 is
-    after p2. So, for instance, when comparing property names, you can use
+    Sort function should return a value greater than 0 if position of @a p1 is
+    after @a p2. So, for instance, when comparing property names, you can use
     following implementation:
 
         @code
@@ -525,9 +525,9 @@ public:
         @param action
             Which action to trigger. See @ref propgrid_keyboard_actions.
         @param keycode
-            Which keycode triggers the action.
+            Which key triggers the action.
         @param modifiers
-            Which key event modifiers, in addition to keycode, are needed to
+            Which key event modifiers, in addition to key code, are needed to
             trigger the action.
     */
     void AddActionTrigger(wxPGKeyboardAction action, int keycode, int modifiers = 0);
@@ -627,7 +627,7 @@ public:
                 const wxString& name = wxPropertyGridNameStr );
 
     /**
-        Dedicates a specific keycode to wxPropertyGrid. This means that such
+        Dedicates a specific key code to wxPropertyGrid. This means that such
         key presses will not be redirected to editor controls.
 
         Using this function allows, for example, navigation between
@@ -676,7 +676,7 @@ public:
                 already fairly large.
 
                 Note that you can also get calculated column widths by calling
-                GetState->GetColumnWidth() immediately after this function
+                GetState()->GetColumnWidth() immediately after this function
                 returns.
     */
     wxSize FitColumns();
@@ -1061,7 +1061,7 @@ public:
 
         @param sortFunction
             The sorting function to be used. It should return a value greater
-            than 0 if position of p1 is after p2. So, for instance, when
+            than 0 if position of @a p1 is after @a p2. So, for instance, when
             comparing property names, you can use following implementation:
 
             @code
@@ -1128,7 +1128,7 @@ public:
 
     /**
         Must be called in wxPGEditor::CreateControls() if primary editor window
-        is wxTextCtrl, just before textctrl is created.
+        is wxTextCtrl, just before the text control is created.
         @param text
             Initial text value of created wxTextCtrl.
     */
@@ -1352,7 +1352,7 @@ public:
     ~wxPropertyGridEvent();
 
     /**
-        Returns @true if you can veto the action that the event is signaling.
+        Returns @true if you can veto the action that the event is signalling.
     */
     bool CanVeto() const;
 
@@ -1438,7 +1438,7 @@ public:
 
     /**
         Call this from your event handler to veto action that the event is
-        signaling. You can only veto a shutdown if wxPropertyGridEvent::CanVeto()
+        signalling. You can only veto a shutdown if wxPropertyGridEvent::CanVeto()
         returns @true.
 
         @remarks Currently only @c wxEVT_PG_CHANGING supports vetoing.

interface/wx/propgrid/propgridiface.h

@@ -83,7 +83,7 @@ wxPG_SORT_TOP_LEVEL_ONLY          = 0x00000200
 
     - wxPropertyGridInterface's property operation member functions all accept
       a special wxPGPropArg id argument, using which you can refer to properties
-      either by their pointer (for performance) or by their name (for conveniency).
+      either by their pointer (for performance) or by their name (for convenience).
 
     @library{wxpropgrid}
     @category{propgrid}
@@ -472,7 +472,7 @@ public:
     */
     wxVariant GetPropertyValue( wxPGPropArg id );
 
-    /** Return's property's value as wxArrayInt. */
+    /** Returns property's value as wxArrayInt. */
     wxArrayInt GetPropertyValueAsArrayInt( wxPGPropArg id ) const;
 
     /** Returns property's value as wxArrayString. */
@@ -481,7 +481,7 @@ public:
     /** Returns property's value as bool */
     bool GetPropertyValueAsBool( wxPGPropArg id ) const;
 
-    /** Return's property's value as wxDateTime. */
+    /** Returns property's value as wxDateTime. */
     wxDateTime GetPropertyValueAsDateTime( wxPGPropArg id ) const;
 
     /** Returns property's value as double-precision floating point number. */
@@ -813,7 +813,7 @@ public:
     wxString SaveEditableState( int includedStates = AllStates ) const;
 
     /**
-        Sets strings listed in the choice dropdown of a wxBoolProperty.
+        Sets strings listed in the choice drop-down of a wxBoolProperty.
 
         Defaults are "True" and "False", so changing them to, say, "Yes" and
         "No" may be useful in some less technical applications.
@@ -824,7 +824,7 @@ public:
     /**
         Set proportion of an auto-stretchable column. wxPG_SPLITTER_AUTO_CENTER
         window style needs to be used to indicate that columns are auto-
-        resizable.
+        resizeable.
 
         @returns Returns @false on failure.
 
@@ -985,7 +985,7 @@ public:
             to wxPGPropertyValuesFlags::DontRecurse to prevent this.
 
         @remarks
-        - This is mainly for use with textctrl editor. Only some other
+        - This is mainly for use with TextCtrl editor. Only some other
         editors fully support it.
         - Property is refreshed with new settings.
     */
@@ -1194,8 +1194,8 @@ public:
 
     /**
         @remarks This function reselects the property and may cause
-        excess flicker, so to just call Refresh() on a rect
-        of single property, call DrawItem() instead.
+        excess flicker, so to just call Refresh() on a rectangle
+        of a single property, call DrawItem() instead.
     */
     virtual void RefreshProperty( wxPGProperty* p ) = 0;
 };