[fix #52699413] Added UpdateLabellable action
bump version to 1.7.0
fixed the root json spec
Added a validation for update labels information
removed duplicated action after merge
Added rake for gemspec for Travis build
[fix 52699413] removed the possibility adding new labels
removed update method from labellable_sequel_persistor
[fix #52699413] Added UpdateLabel action

and removed UpdateLabellable action.
inherit parameter related errors from InvalidParameters

also refactored the action execution code
changed the error message for insufficient information
Use lims-api v2.4
added more tests for invalid parameters
Merge pull request #39 from ke4/52699413_add_update_action_for_labellable_resource

52699413 add update action for label resource