Merge actual-dt-characterization, dt-characterization, and swim-shady-dt

[ProfessorAtomicManiac]

actual-dt-characterization had SysId code for Hammerhead, which is copied over in Drivetrain.java dt-characterization had SysId code for Swim Shady but is identical to actual-dt-characterization except for the ports. I put a flag to easily switch between the constants. swim-shady-dt was created so we can test the now defunct bangbot code on Swim Shady for auto testing. There is no need to grab any code from that branch. After this merge, all three branches can be safely deleted.

[FriedLongJohns]

We can delete other branches after we test in WS that this works.

[ProfessorAtomicManiac]

I'm going to delete swim-shady-dt, that doesn't need to be tested.