Nearly done
Now reads all the #DEFINEs statements, adds them to the configuration file, and allows to pass them in the cmake call
Added conditional inclussion of packages
Added conditional support for source files and custom VAPIs
Forgot to add this file
Now supports conditionals on nearly all commands
Now puts all the condition params and all the defines as OPTIONs for CMAKE
Merge branch 'conditional'
Updated documentation with conditional compilation