Update .gitignore

Commit 353719a2ddec4d6a8458ee42af37514fedbd80bf adds gmarshal_funcs.c,
gmarshal_funcs.h.

Commit a223b6b426c1897977b987d0ddce434afba604da adds /bin/, barnowl,
tester and removes barnowl.bin, tester.bin.

Automake 1.13 (which enables the parallel testsuite harness by
default) adds runtests.sh.log, runtests.sh.trs, test-driver,
test-suite.log.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Get rid of all our embedded copies of Module::Install

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Really support building Perl modules from a separate builddir

Signed-off-by: Anders Kaseorg <andersk@mit.edu>