This task is created to improve performance of Project parsing:
 - one time lexing of the file
 - separated Lexer and preprocessing
 - universal APT-based structure of lexed file
 - universal traversing over APT
Advantages:
 - language independent preprocessing
 - intellisence #include handling (PCH-like support)
 - common infrastructure to be used by preprocessor code folding and parsing
(APT Visitor extension)
 - guard blocks
Other TODO possibilities:
 - C/C++ independent language keyword filters
 - syntax higlighting with understanding of Macros using
 - color highlighting of inactive preproc branches