* update demo app to Xcode5
* changed min demo app os ver to 6.0
+ added a new protocol "Ignore" to completely ignore a property from the JSONModel workflow
* added Ignore example
* prepare for 0.9.3
* bumped up to 0.9.3
expose selector JSONFromURLWithString:method:params:orBodyString:completion:
replace add with set because it needs to be possible to override the default headers

when using "add", the headers are merely concatenated anyway. This can easily be achieved still & therefore this change does not remove any ability
resolves #97
resolves #95
Merge pull request #96 from BillinghamJ/issue-#96

[Req] Expose JSONFromURLWithString in JSONHTTPClient
Merge pull request #97 from BillinghamJ/issue-#97

[Req] Expose method for replacing all headers
Merge branch 'master' into issue-#95
Merge pull request #95 from BillinghamJ/issue-#95

JSONObjectBlock doesn't allow for NSArrays
correction to null check

covers cases where the object is NSNull, but not nil. NSNull != nil
aha. Did not realize we had an isNull function. Using that now :)
Merge pull request #99 from BillinghamJ/null-check-bug

correction to null check
* more samples
* style fixes
* style fixes
Use globalKeyMapper in serialization process too (toDictionary / toJSONString)