Fix various items to run unit tests within XCode 6 again

- Upgrade to latest OCMock 3.1 so we can test against 64bit cpus
- Fix StringsTest.m XCTAssertEqual no longer supports c structs,
  convert to use NSEqualRanges wrapped within an XCAssertTrue
- Switched the originalText within Task.h from a weak pointer to a
  strong to make existing test cases pass again. Not sure if this
  was broken before hand or is something new with a later revision
  of iOS