2014-12-30 tengqm <tengqim@cn.ibm.com>
	* db/api.py: remove action_update interface function to allow
	  stricter checking of action status changes.

2014-12-29 tengqm <tengqim@cn.ibm.com>
	* db/sqlalchemy/models.py: added 'node_count' to cluster class.
	* db/sqlalchemy/migrate_repo/versions/001_first_version.py:
	  added 'node_count' to cluster class.

2014-12-29 tengqm <tengqim@cn.ibm.com>
	* TODO: Added some test cases jobs.

2015-01-02 liuhang <hangliu@cn.ibm.com>
	* TODO: Remove DB action APIs task.
	* db/api.py:
	  add 'action_add_dependency', 'action_del_dependency'
	  remove dependency api without transaction.
	* db/sqlalchemy/api.py:
	  add 'action_add_dependency', 'action_del_dependency'
	  remove dependency api without transaction.