Use compressToUTF16 instead of default compression

We do this to stop the bug that arises that can cause an error with the
compressed string in encodeURIComponent
Update middleware to decompresseFromUTF16

This is to match the compression used in the compressKeys functions on
the clientside.
Merge pull request #1549 from jsbin/feature/encrypt-save-post

Feature/encrypt save post