synchronize includepath entries etc between .pro file and CDT settings

Better integration with the project's Include Paths and Symbols during .pro file import: the integration plugin automatically adds the include paths for Qt in the project's include paths and symbols, which is a good thing already, but it doesn't extract those contained in the .pro files. If you have extra include paths for your project, and symbols defined e.g. for DLL export macros, the indexer will not recognize them and it will be confused.

These can still be added manually, but it can become tedious for big projects, and it feels like a duplication of work and information considering the information is already in the .pro files.