Having an executor within container package creates
potential import cycling. This patch moves it to a separate
package which can be used to conveniently store all the executors
at one place.
Change-Id: Ibd07c2ba46d1971604bdbd9e5e360759bb68a659
Signed-off-by: Ruslan Aliev <raliev@mirantis.com>
Relates-To: #432
01266f036e