Merge pull request #24 from mholden8/master

Use PythonMetricsCalculator module to calculate all metrics.
Attempting to fix build errors in Linux (remove references to Qt from logic).
Removing the python metrics tests from the Perk Evaluator and restoring the generic tests.
Modifying update system to use Qt signals and slots.
Use specific signals and slots for different events.
Merge pull request #25 from mholden8/SignalsSlots

Fix widget updating
Re #26: Attempting to fix build errors associated with the Transform Selection widget.
Associate roles with each transform. Transforms should be analyzed with respect to metrics that are suitable for their respective roles.