Revise implementation of orphaned object deletion to avoid inappropriately deleting when the `modificationKey` attribute optimization is in use. refs #1328
Test for #1328

Also added Meeting and Party to Data Model for testing Dynamic Mapping with Core
Data models.

Signed-off-by: Blake Watters <blakewatters@gmail.com>
Fix issue with relationship traversal when gathering objects for orphan comparison
Rework cancellation behaviors so that the failure block and error are invoked.

* Add new error code for cancelled operations
* Ensure the failure block is called when cancelled
Eliminate inappropriate static local in favor of an ivar
Add license boilerplate
Add missing documentation for `modificationKey`
Add support for assigning objects to a particular persistent store on a per entity mapping basis. closes #1386
Remove unreachable code for parsing dates. closes #1385
Update installation recommendations for CocoaPods for the modern era
Migrate unit testing infrastructure from xcoder to xctool. Add Travis CI integration
Add Travis CI build badge to README.md
Add shared schemes so that Travis can execute the build
Drop docs publication from cibuild script
Add explicit workspace argument to xctool
Fix issues with generation of ISO-8601 date strings with UK locale + 24 hours disabled on device

If you switch to the United Kingdom locale and then disable the 24 hour clock RestKit will emit date strings such as "2013-06-10T11:55:00 PMZ"

* Add locale option to `RKISO8601DateFormatter` to enable you to specify the locale for generation.
* Update preferred date formatter to use `en_US_POSIX` locale to ensure dates generated are in UTC 24 hour notation
* Do a bit of cleanup to the ISO-8601 date formatter. It's quite a mess in there.
Bail our of creating objectRequestOperation when unable to find a URL.
Bump Gem deps
Add shared schemes and rework CI test scripts
Fix issue where an empty mapping result would not trigger orphaned object deletion