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/thread.cpp

@@ -64,10 +64,8 @@
     (defined(__BORLANDC__) && (__BORLANDC__ >= 0x500)) || \
     (defined(__GNUG__) && defined(__MSVCRT__))
 
-#ifndef __WXWINCE__
     #undef wxUSE_BEGIN_THREAD
     #define wxUSE_BEGIN_THREAD
-#endif
 
 #endif
 
@@ -338,7 +336,6 @@ private:
 
 wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount)
 {
-#if !defined(_WIN32_WCE) || (_WIN32_WCE >= 300)
     if ( maxcount == 0 )
     {
         // make it practically infinite
@@ -352,7 +349,6 @@ wxSemaphoreInternal::wxSemaphoreInternal(int initialcount, int maxcount)
                         maxcount,
                         NULL            // no name
                     );
-#endif
     if ( !m_semaphore )
     {
         wxLogLastError(wxT("CreateSemaphore()"));
@@ -391,7 +387,6 @@ wxSemaError wxSemaphoreInternal::WaitTimeout(unsigned long milliseconds)
 
 wxSemaError wxSemaphoreInternal::Post()
 {
-#if !defined(_WIN32_WCE) || (_WIN32_WCE >= 300)
     if ( !::ReleaseSemaphore(m_semaphore, 1, NULL /* ptr to previous count */) )
     {
         if ( GetLastError() == ERROR_TOO_MANY_POSTS )
@@ -406,9 +401,6 @@ wxSemaError wxSemaphoreInternal::Post()
     }
 
     return wxSEMA_NO_ERROR;
-#else
-    return wxSEMA_MISC_ERROR;
-#endif
 }
 
 // ----------------------------------------------------------------------------
@@ -947,11 +939,8 @@ unsigned long wxThread::GetCurrentId()
     return (unsigned long)::GetCurrentThreadId();
 }
 
-bool wxThread::SetConcurrency(size_t WXUNUSED_IN_WINCE(level))
+bool wxThread::SetConcurrency(size_t level)
 {
-#ifdef __WXWINCE__
-    return false;
-#else
     wxASSERT_MSG( IsMain(), wxT("should only be called from the main thread") );
 
     // ok only for the default one
@@ -1015,7 +1004,6 @@ bool wxThread::SetConcurrency(size_t WXUNUSED_IN_WINCE(level))
     }
 
     return true;
-#endif // __WXWINCE__/!__WXWINCE__
 }
 
 // ctor and dtor