Change viz scripts to call functions in fsate; add consistent plot style theme

[bolotinl]

Changes

• Use functions from fs_algo_train_eval.py in fs_perf_viz.py to create data viz
• Change "perf map" to "pred map" (perf could mean a lot of different types of performance (predicted? actual?)) so this clarifies that the maps are of predicted values
• Add .mlpstyle file which customized the style theme of the generated plots in fs_perf_viz.py

Testing

The viz_config.yaml should require little to no customization, though it is customizeable in terms of which plots will be generated.

1. python fs_perf_viz.py "/full/path/to/viz_config.yaml"

[glitt13]

@bolotinl this is the spot where pred_map should be changed to perf_map