Updates to make rails 4 happy with minitest 5:

+ Namespace changes, overhaul of runners.
+ Internal ivar name changes
- Removed a logger globally applied to tests that spew everywhere?!?
+ Override Minitest#__run to sort tests by name.
+ Reworked testing isolation to work with the new cleaner architecture.
- Removed a bunch of tests that just test minitest straight up. I think these changes were all merged to minitest 4 a long time ago.
- Minor report output differences.
tweak dependencies
oops. I should have only required minitest, not minitets/autorun. muscle memory.
Merge pull request #10527 from zenspider/squishy_minitest5

Squishy minitest5