docker bootstrap service commands

docker bootstrap service commands

This patch guards db syncs and initialization code from executing
on multiple nodes at the same time by using the new
bootstrap_host_exec script. This helper script checks to make
sure the container is executing on the "bootstrap host" for the
specified service (arg 0) and then if it matches runs the
specified command.

Depends-On: If25f217bbb592edab4e1dde53ca99ed93c0e146c
Depends-On: Ic1585bae27c318bd6bafc287e905f2ed250cce0f

Change-Id: I0c864ca093ea476248b619d8c88477ef0b64e2eb
Closes-Bug: 1688380