Support deleting individual changeset
Summary:
add support in purge_cache.php. We might want to add support
for maniphest comments and differential comments later.
Test Plan:
- purging all worked
- purging individual changeset worked
- when input is not integer, correct error message reported
Reviewers: epriestley, btrahan, nh
Reviewed By: nh
CC: nh, aran, jungejason, epriestley
Maniphest Tasks: T683
Differential Revision: https://secure.phabricator.com/D1372