fix empy on travis again.
Added regression test
Fix get_reverse_depends to behave like the docstring. Ensure that dependent capabilities are stopped when stopping their base capability.
Traverse dependency graph and stop implicit dependents.
Merge pull request #37 from esteve/stop-dependencies

When stopping a capability, stop all dependent capabilities as well
working on reference counting, not done
basic working version of use/free capability
fixup
fixup
add bondpy to travis deps
fix travis
fixes wait_for_service and bonds storage