Migrate from mongodb-tools to christkv/mongodb-topology-manager

[imlucas]

@christkv rewrote all of this in a new beautiful package recently. We should replace our current usage of christkv/mongodb-tools to instead use christkv/mongodb-topology-manager.

• Switch to mongodb-topology-manager
• Delete https://github.com/mongodb-js/mongodb-tools
• Finally close Stall after downloading mongodb version #51

[imlucas]

@chistkv

Runner has been most successfully leveraged as global mocha hooks for before/after:
https://github.com/mongodb-js/runner#mocha

Actually using mongodb-tools in a gnarly way currently. lib/index.js
acts as a parent supervisor/child process ctl to simplify config options into more human names/defaults.

lib/worker.js is the childprocess lib/index.js manages.
This is where mongodb-tools code is actually called. After starting, the worker also listens for IPC messages from the parent which
are then translated into calls against the various mongodb-tools#Manager apis.

[imlucas]

Don't think this will happen