Naive mirroring implementation
keys and secrets
Added config entry for source_index
Reworked source_lookup, storing json/ancestry/etc locally, removed decorator (obsolete)
tags: Factor get_tags out of the _get_tags endpoint

Gettings a nicely-parsed list of tags is useful internally, so pull
the tag-listing logic out into it's own function.  The decorated
endpoint behind GET /v1/repositories/<path:repository>/tags is *not*
useful internally, so prefix that function with an underscore.

To convert the get_tags iterator to a dictionary, I've used a dict
comprehension [1], which landed in Python 2.7 and 3.0.  I couldn't
find any docs on docker-registry's minimal supported Python version,
so I imagine compatibility with ancient Pythons is not high on the
agenda.

[1]: http://www.python.org/dev/peps/pep-0274/
tags: Factor delete_tag out of the _delete_tag endpoint

Deleting a tag (and raising the associated signal) is useful
internally, so pull the tag-deleting logic out into it's own function.
The decorated endpoint behind
DELETE /v1/repositories/<path:repository>/tags/<tag> is *not* useful
internally, so prefix that function with an underscore.
Tags are mutable, they shouldn't be stored on mirrors
Added tags caching support (with TTL)
Moving test_layers test to cStringIO instead of StringIO
Merge pull request #250 from dotcloud/tests-cstringio

Moving test_layers test to cStringIO instead of StringIO
pep8 fix
Tags cache ttl expressed in seconds, small bugfixes, minor improvements
Workaround headers too large problem with Glance v1 api
Switch order of add and pip install

This just updates the Dockerfile to take advantage of the ADD caching
added in 0.7.3 to speed up docker builds of the registry.

Docker-DCO-1.1-Signed-off-by: Phil Kates <me@philkates.com> (github: philk)
Merge pull request #258 from ewindisch/glance-headers-too-large

Workaround headers too large problem with Glance v1 api
added ignore files
Reimplemented cleaned up mirror decorator
Applied source_lookup decorator on relevant methods
Added tags lookup decorator (and caching logic). Cleanup.
Merge branch 'master' of github.com:dotcloud/docker-registry