show cpanm log on dependency errors
Add service inheritance sugar
Support inheriting services in parameterized containers
Make the container sugar add subcontainers even without a block
Simplify the container sugar
Implement container inheritance
Simplify the container sugar further

There was only one place branching on $name_is_obj left, so we might as well get
rid of the temporary.
Containers owned by other containers aren't subcontainers
Test subcontainer inheritance