1. wxLongLong and wxDateTime compilation fixed for the compilers without native

1. wxLongLong and wxDateTime compilation fixed for the compilers without native
   "long long" type (and some code in timercmn.cpp too)
2. wxDate and wxTime reimplemented using wxDateTime (old versions tagged as
   OLD_DATE_AND_TIME)
3. wxString::To(U)Long and ToDouble added and documented
4. bug with combobox in toolbar (drop down list wasn't dismissed) fixed
5. several wxDateTime::Parse() functions implemented
6. added support for coloured buttons under MSW (not completely finished)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@5043 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775