All hooks files which were identical and had no second group of
identically named hook files have been moved to a new hooks/common
directory and now have symbolic links to the new single file at their
old locations.
Also slightly modified to make this work:
* Makefile: copy new hooks/common directory
* Some tests: ignore new hooks/common directory
This makes t/no-tabs.t pass.
I'm responsible for some tabs in previous patches, so this
fixes mine also :)
Note that I find this test silly, but "dura lex, sed lex"...