PHTracking extension

[garg02]

This PR is 98% independent of #333, but until sending hub bounds to spoke is finalized, convergence tracking that require hub bounds won't work. I have disabled the specific tracking args in cfg_vanilla.py so the tests will run fine.

Notes of changes that have been made by file
phtracker.py:

• Implemented tracking as an extension;
• As some of the tracking code (bounds and nonants) could be used for other optimizers besides PH, maybe we should make subclasses of TrackedData for each type. Thoughts?

cfg_vanilla:

• Used extension_adder to simplify the process of bridging command line arguments with ph options

farmer_cylinders.py:

• using extension_adder so extensions can also be added from cfg_vanilla

primal_dual_converger.py

• Implemented tracking

lagranger_bounder.py and lagrangian_bounder.py

• initialize iteration variable earlier so tracker can access
• call extensions post_loops()

converger.py, extension.py, phbase.py, and spopt.py

• added hooks to call extension and converger methods

config.py

• added command line arguments to use wxbar reader and writer and PHTracker

examples/run_all.py

• testing changes