Changes to the file .gitignore

I made some changes to the file .gitignore, because in you project there are some big files (aroung 34.5Mb) that we don't use and that are generated by the Visual Studio on compiling. I added some file extentions to be ignored by Git. 
These file extentions are .ipch, .pdb, .ilk, .idb, .obj, .tlog