+ Minitest.init_plugins passes down options.
+ Minitest.load_plugins only loads once.
Moved most of minitest/pride into minitest/pride_plugin.
Moved pride cmdline option handler into pride_plugin.rb
minitest/pride now just activates pride.
- Fixed minitest/pride to work with rake test loader again. (tmiller)

[git-p4: depot-paths = "//src/minitest/dev/": change = 8475]
Fixed test_setup_teardown_behavior for mt5. (phiggins)
[git-p4: depot-paths = "//src/minitest/dev/": change = 8476]