adding eddy viscous damping to TDC

[pmocz]

No description provided.

[Debraheem]

Things left to do:

-move alfam from controls_dev.defaults to controls.defaults?
-add documentation on what Eq and Uq represent, and document other TDC controls.
-add condition that skips calculating Eq and Uq if .not. v_flag = .true.
-minor clean up of commented quantities and spacing.
-run a full test on the test_suite.

[Debraheem]

MESA-TDC_rehash.pdf
I've attached a re-hash of some of Adam's notes on MESA-TDC versus RSP (neglecting the luminosity equation for this discussion and the differences therein). In this PR, we have added the Eq and Uq terms back into the equations to bring MESA-TDC in closer agreement with MESA-RSP.

[Debraheem]

lots of clean up and testing needed on my end, but I would like to make these test cases work before merging this branch.

[Debraheem]

Some of the RSP test_cases need checked as well, as I have confirmed some of them decay instead of grow in the current branch, hence the initial conditions need tweaked slightly.