[#5] Added `tasks` command to print tasks.

Added tasks command to print tasks, fixed task command to properly
set values, added ability to run one command from program args.
[#9] Refactored metrics storage for histograms

Updated metrics storage layer to allow for histogram storage of duration
values.  Update tests to match new metrics implementation.  Created new
projects module for projects/tasks.  Moved MaxifyCmd to ui module.