Switch to argparse and use argcomplete to deal with options with fixed list of possibilities

[mattb112885]

I should be using argparse rather than optparse because the latter is obsoleted. Also, it works with this package:

https://github.com/kislyuk/argcomplete

I see the following uses (at least) for such a package:

1 - Automatically suggest run IDs for the many functions that require input of a single run ID
2 - Automatically suggest scoring metrics for the functions that only allow use of a specific set of scoring metrics.

Would it get confusing if I use such an ability for some arguments but not for most?