Merge pull request #1351 from jlipps/master

couple misc fixes
Made test.sh sh compatible (removed bashisms). Made test.sh not rely on mac-only tooling. Small documentation tweaks in readme and contributing doc.
Merge pull request #1353 from filmaj/sh-compat

Shell compatibility w/ test.sh
Change name of capabilities method for sauce_example.rb to prevent us trampling a protected method
Merge pull request #1354 from DylanLacey/master

Don't monkey-patch "capabilities" as this is now apparently a defined method