Larger cleanup in preparation for refactoring
- More objects moved to singletons
- Slightly improved marking of changed tabs (works with undo at least)
- Slightly better save (not save as, haven't looked at this yet), since saving when no change will only lead to more compile time
- Refactoring moved to separate class (ClangViewRefactor).
- More use of boost::filesystem so that it works on Windows. Probably some more places that needs this.
Also remember latest version of libclangmm (creating pull request right after this). Some more cleanup there.