mono/mono — pull request #1140 by ztzg (2014-06-30 22:01:35+00:00)
Title: [dist] Do not include .git link files in dist tarball

Recent versions of Git co-host submodule `GIT_DIR`s in `/.git/`
by default, and write their relative path into `/.git`,
which is a regular file:

$ ls -l external/cecil/.git
-rw-r--r-- 1 foo bar 42 Jun 16 12:50 external/cecil/.git
$ cat external/cecil/.git
gitdir: ../../.git/modules/external/cecil

Relax the expression in `Makefile.am` to also delete these (broken)
"symlinks" when preparing a distribution tarball.