Fix session cleanup without LIMIT support

In some distributions, 'LIMIT' is not supported with 'DELETE'. On those
systems, retry without 'LIMIT'. (refs #373).
Fix git repository name inconsistencies (fixes #296)

The following changes have been made to fix this:
 * Accept both '<repo>.git' as well as '<repo>' when updating hooks
 * Show repo names instead of dir names for old git hooks
 * Change function name to reflect this change