Remove Windows CE support

Windows CE doesn't seem to be supported by Microsoft any longer. Last CE
release was in early 2013 and the PocketPC and Smartphone targets supported by
wxWidgets are long gone.

The build files where already removed in an earlier cleanup this commit
removes all files, every #ifdef and all documentation regarding the Windows CE
support.

Closes https://github.com/wxWidgets/wxWidgets/pull/81

src/msw/textmeasure.cpp

@@ -105,11 +105,9 @@ void wxTextMeasure::DoGetTextExtent(const wxString& string,
         wxLogLastError(wxT("GetTextExtentPoint32()"));
     }
 
-#if !defined(_WIN32_WCE) || (_WIN32_WCE >= 400)
     // the result computed by GetTextExtentPoint32() may be too small as it
     // accounts for under/overhang of the first/last character while we want
     // just the bounding rect for this string so adjust the width as needed
-    // (using API not available in 2002 SDKs of WinCE)
     if ( len > 0 )
     {
         ABC widthABC;
@@ -131,7 +129,6 @@ void wxTextMeasure::DoGetTextExtent(const wxString& string,
         }
         //else: GetCharABCWidths() failed, not a TrueType font?
     }
-#endif // !defined(_WIN32_WCE) || (_WIN32_WCE >= 400)
 
     *width = sizeRect.cx;
     *height = sizeRect.cy;