Fixes for code analysis warnings and strict const-qualification conformance (/Zc:strictStrings)

git-svn-id: http://svn.code.sf.net/p/wtl/code/trunk/wtl@591 4beafcb9-bf40-0410-b8f5-b741cf90ec0e
atlfind.h: UseShadowBuffer() - Use AtlGetCommCtrlVersion() instead of GetProcAddress() for ComCtl32.dll

git-svn-id: http://svn.code.sf.net/p/wtl/code/trunk/wtl@592 4beafcb9-bf40-0410-b8f5-b741cf90ec0e
Misc improvements: initialization, undefined messages, better #ifdefs

git-svn-id: http://svn.code.sf.net/p/wtl/code/trunk/wtl@593 4beafcb9-bf40-0410-b8f5-b741cf90ec0e