fixes #3826: no more sql errors when trying to search for environments (also domains, operatingsystems, and models)
fixes #4115 - added missing LICENSE file
fixes #3828 - set language locale for API messages and error responses
fixes #3909 - add disassociate and bulk action disassociate to interface
fixes #3955 - added param_true? and snippet_if_exist template methods
fixes #4152 - fix syntax error in _form.html.erb for hosts and hostgroups