Deletes all pipelines
		Args:
			returns		OK for overall success or last error code, resp data.

def delete_all_pipelines(self):
		'''Deletes all pipelines
		Args:
			returns		OK for overall success or last error code, resp data.
		'''
		code, data = self.get_pipeline()
		if code == requests.codes.ok:
			for pl_data in data:
				c, d = self.delete_pipeline(pl_data['pipelineKey'])
				if c != requests.codes.ok:
					code = c
					data = d
		return code, data