Review/update .gitignore files

Review/update .gitignore files

Merge potentially useful patterns taken from other projects.

Some application specific patterns were move to their respective directories.

The only noticeable change is that *.patch is ignore to prevent accidental
checkin of patches. The pattern "test-driver" could not be found and was
removed.

The test directory had not been updated since the move of all test cases
in a single binary.

Signed-off-by: Gaetan Nadon <memsize@videotron.ca>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>