Added Community.from_slug method
Added REST API to get community with all its members.
Moved converting participant to JSON to utils.json
Test refactored
use cls.db instead of passing website.db as argument
move Participant.get_members_of_community() into Community.get_members()
move gittip.utils.json.from_participant() to Participant.to_dict()
don't make costly DB requests by default
whitespace
Added pagination to community members REST API
coding style
add test for max limit
refactor code
don't list users who have left the community, and fix ordering
query by `slug` instead `name`
create index on communities.slug

The test query I tried on the production DB got about 30 times faster.
remove commented code
add total count of members to response
Merge pull request #2430 from gittip/members-json

 API to list members of a community. Resolves #2395
merge branch.sql into schema.sql
Bump version to 13.1.5