Add qmake generated files to .gitignore.
Add qmake generated files to .gitignore.

Add source files generated by qmake for automatic static plugin
imports to .gitignore.

Change-Id: I8f7d72827b4fcea3811815a088012f92f4f83e38
Reviewed-by: Oswald Buddenhagen <6a8868beda3e139b5ac22b2534a23d3e6ba81819@digia.com>

kobolabs/qtimageformats,kobolabs/qtimageformats,kobolabs/qtimageformats,kobolabs/qtimageformats