Squashed commit of the following:

commit 47c5abbcdf1245e13e9140109f4990e764e889fb
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 17:24:56 2013 -0500

    Whoops.. RailsDiff only goes back to 3.0

commit 4a7fc450710676ed2f4a12e52a22cc2113e43f57
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 17:22:47 2013 -0500

    Actually add link to RailsApps' guide

commit 033ca974cf5feb58f3072f79af8a99ad5341d89a
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 17:20:23 2013 -0500

    Make RailsDiff links inline w/ checklists; add additional guide links to Other Resources

commit 2ec238a3839f7f8429eae63c3f337354fdda20c0
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 16:59:18 2013 -0500

    Ruby off Rails => Ruby Off Rails

commit edc0755a85eb1e8e0aa75271aec864f6c3f53214
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 16:56:32 2013 -0500

    README whitespace; fix typo

commit d70de1a570226aaad508ecbc5d64436f3a6537ad
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 16:54:14 2013 -0500

    Add "Other Resources" section w/ RailsDiff link

commit c911ac17de48fa39a8908460504c04bee944a71a
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 16:53:50 2013 -0500

    Fix typo

commit bb4754979afa49dc11a2982efd9e6f1811f6e61b
Author: Joshua Rieken <joshua@joshuarieken.com>
Date:   Sat Jun 22 16:53:36 2013 -0500

    Whitespace