Add new .gitignore entries for Automake 1.13 tests

Automake 1.13 creates a bunch of new build artefacts:
- bin/test-driver, a script for running tests.
- *.trs files for every "make check" test result.
- *.log files containing the output of every test run by "make check".

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

bin/.gitignore

@@ -6,3 +6,4 @@ install-sh
 ylwrap
 compile
 ar-lib
+/test-driver