Update scripts for Mobile Services changes on 11/24/2013

http://blogs.msdn.com/b/azuremobile/archive/2013/11/24/what-s-new-in-azure-mobile-services-1-6-4247.aspx?utm_source=twitterfeed&utm_medium=twitter
Make use of Optimistic concurrency.

Split Sync logic into separate class.
More validation.
Remove duplicate code.
Fix Null values in database.
Fix bug with column names.
Fix bug with sqlite column types.
Split sync logic and network to separate class.

Improved network abstraction in Http.cs
Sync now updates the database.
Move code to helper classes.
Change id type to string instead of Guid, because mobile services sdk
doesn't like it.
Update tests. Fix bugs in Remove.
Fix bugs with old "timestamp"strings.

Fix Http keeping response alive.
Fix sending no content type.
Fix version uris.
Fix update sql.