pipeline history api
agent job run history api
job history api
stage history api
handle empty data in api models
config api: material listing
to_json not required during json rendering
config api: revision listing
config api: diff b/w 2 commits
pipeline status api
config api: list pipeline configs
history apis: add offset param coverage to controller specs
use date.getTime() instead of date.toString() during ruby model initialization
material commits api
material api: looping through groups directly instead of getting names & then getting pipelines in group
material api: should list material only once during listing
pipeline history + angularjs + api usage
Revert "pipeline history + angularjs + api usage"

This reverts commit 447979f99f5698f214db68cd59bd6d7c5b1ff8bf.
incorporating feedback to PR 381
merge with master