Add maestro play feature

[jsemler]

This feature would introduce a new config file for specifying a Maestro study to run along with available run options. This would make it easier to run more complex Maestro studies more easily while still decoupling run configurations from the study spec.

The following Maestro study could then be written to a new config file:

-  study: study1.yaml
   pgen: pgen1.py
   throttle: 20

The new file could also allow multiple Maestro study specs to be configured.

-  study: study1.yaml
   pgen: pgen1.py
   throttle: 20

-  study: study2.yaml
   pgen: pgen2.py
   throttle: 10

The studies would be launched via a new option:

maestro play <filepath>

Thoughts, feedback, and suggestions are welcome.

[jsemler]

Tagging @crkrenn and @FrankD412

[jwhite242]

pgen args? maybe something like this:

- study: study1.yaml
  pgen: pgen1.py
  pgen_args:
    - arg1: val1
    - arg2: val2

[jsemler]

@jwhite242 -- Excellent suggestion. I think that format would work well.

[FrankD412]

I've been thinking about this over the last few days. I wonder if it might be worth doing something similar to a study specification and having a description and some high level settings.

I feel like these should be called ensembles...

name: <name>
description: Ensemble of studies to test x, y, z
OUTPUT_PATH: <central path to store studies>

studies:
- spec: <path>.yaml
  pgen: pgen1.py
  pgen_args:
    - arg1: val1
    - arg2: val2