On the ra-git branch: Add standard ignore patterns.

* subversion/libsvn_fs_git,
* subversion/libsvn_ra_git: Update the svn:ignore property.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/ra-git@1846072 13f79535-47bb-0310-9956-ffa450edef68