added comments
fixed comments
fixed text
fixed comments
added primary key to option_collection
added request_ids reference to job_guid description
Merge pull request #10 from mozilla/schema-comments

schema comments
tests use cache versioning to keep isolation
remove cache.clear() from tests setup/teardown
remove unused import
Merge pull request #11 from mozilla/add-memcached-setup

add memcached setup
merge changes from master into sql-datasource