Reverted unused core data model version

git-svn-id: http://ios.svn.wordpress.org/trunk@4024 7d847f7c-ffe1-4a24-85be-b788d016d96a
Refactor autosave interval into a constant for easy tweaking

git-svn-id: http://ios.svn.wordpress.org/trunk@4025 7d847f7c-ffe1-4a24-85be-b788d016d96a
Less aggressive autosave values when using 3G

git-svn-id: http://ios.svn.wordpress.org/trunk@4026 7d847f7c-ffe1-4a24-85be-b788d016d96a