[event_tags] added "tags" (array of strings) to event hash
[all_entities] allow contacts to be associated with a common entity "ALL"
Merge pull request #453 from portertech/event_tags

Added "tags" (array of strings) to event hash
Merge pull request #454 from portertech/all_entities

Allow contacts to be associated with a common entity "ALL"
prepare 0.8.7 release