Add post_regtest_checks check_headers_and_includes to dist_noinst_SCRIPTS.

Also allow a .git directory in check_headers_and_includes to help
people using a git mirror of valgrind/VEX svn.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13601 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/tests/check_headers_and_includes b/tests/check_headers_and_includes
index 2b9caf4..4a75ce8 100755
--- a/tests/check_headers_and_includes
+++ b/tests/check_headers_and_includes
@@ -49,6 +49,7 @@
 my %dirs_to_ignore = (
     ".deps" => 1,
     ".svn" => 1,
+    ".git" => 1,            # allow git mirrors of the svn repo
     ".in_place" => 1,
     "Inst" => 1,            # the nightly scripts creates this
     "VEX" => 1,