0.123    2014-11-13
	 - add support for retrieval of one task variable
0.122	 2014-10-16
	 - Extend Activiti::Rest::Error
	 - Bug in Activiti::Rest::Error : response content only used in Activiti::Rest::Error::InternalServerError, rest uses response message
0.121    2014-10-08
	 - add default header "Accept: application/json" to ensure that Activiti always returns json (in newer version XML can be returned)
