Expanded Testing Capabilities to support GLWACSO Test Case

[ptomasula]

Problem:

The current testing infrastructure for comparison with HSPF and HSP2 consists of the single test10 scenario. With the addition of the water quality modules (reference PR #39), the testing scenarios should be expanded to include models which utilize the water quality features.

Solution:

This branch makes minor tweaks to the existing unit testing class developed by @tong.zhai to support the GLSACSO test case.

Testing:

The revised test class was executed for the GLWACSO scenario to confirm that a test_report_conversion.html document would be correctly generated.

Addresses:

• Expand & automate testing system respec/HSPsquared#31

[ptomasula]

Latest round of commits restructures the core RegressTest class to make it more performant and easier to maintain and extend in the future. Summary of updates include:

• Revise methods to have single (or near single) responsibly.
• Separated HTML generation from comparison logic.
• Added multithreading support to combat slow runtime, which is due to IO bound operations.
• Added logic to filter on subset of activities, operation, ids, and/or time codes. Helpful in debugging testing code, or running a quicker targeted report (as opposed to one for all parameters).
• Restructured test class to only support single test scenario. Multiple test scenario will now need to be handle through looping separate class instances.
• Added type hints to RegressTest and HDF5 classes.

[ptomasula]

@tredder75 @aufdenkampe
I just merged in the latest model code updates from @tredder75's wq-updates-tmr (see PR #48). Next step is to run an updated comparison for GLWACSO, and if all goes well, I'll complete this pull request and merge the updated testing code back into the develop branch.