2.1.0: Some mayor refactoring.

2.1.0: Some mayor refactoring.
  - Don't use boost::noncopyable, use CASPAR_NO_COPY instead.
  - Use enum_class instead of regular enums.
  - Use FORWARDx to forward declare classes inside namespaces.
  - Forward declare class in active namespace inline.
  - Move some general classes into common root.
  - Renamed string to utf.
  - Removed lexical_cast_or_default, just use regular lexical_cast.
  - Misc...

git-svn-id: https://casparcg.svn.sourceforge.net/svnroot/casparcg/server/branches/2.1.0@2109 362d55ac-95cf-4e76-9f9a-cbaa9c17b72d