adding container tests, some cleanup
removing logger setupgit st
merging matt's work and removing handle_result from dep-providers
Merge pull request #47 from onefinestay/result-callback

using a result-callback instead of a handle_result on the dependency-prviders
moving worker function out to make code more readable
removing an obsolete TODO
addressing codereview, mainly cleaning up my lazy namings and insufficient comments
Merge pull request #46 from onefinestay/container-tests

container tests