Update gitignore rules

As per Michael's comment, gitignore should not ignore a couple of real
files from the autotools/ directory.

Reviewed-by: ultrotter

.gitignore

@@ -13,7 +13,7 @@
 /TAGS
 /aclocal.m4
 /autom4te.cache
-/autotools
+/autotools/
 /config.log
 /config.status
 /configure
@@ -23,6 +23,10 @@
 /*.tar.bz2
 /*.tar.gz
 
+# overrides
+!/autotools/ac_python_module.m4
+!/autotoosl/docbook-wrapper
+
 # devel
 /devel/clean-cluster
 /devel/upload