Check in the doxygen files for building standalone gil docs.

They are mostly unchanged. I've just changed some of the paths.

[SVN r52726]

libs/gil

@@ -1 +1 @@
-Subproject commit 66ebcd63218445e3e6349925ddaf096234526171
+Subproject commit 2f61fb2dd18a10ac9e0d7b5d9f757e7170cb66f5