Now that we don't build Lift for 2.8.x, we can add the second parameter to all the deprecated messages we have.
Thus would eliminate the compiler warnings we get at build time.
* Fixed #1292 - added version to the @deprecated messages.
* Removed more compiler warnings.
* Changed S.respondAsync to use RestContinuation.async (and removed deprecated usage)
This pull request also removes the deprecated @serializable annotation and instead extends each class with Serializable
case classes already mix in Serializable , so that is why you would see I removed the annotation but did not add the mixin. (You get an error similar to "added xyz twice..."
I also changed calls to error() for sys.error() and I changed a few S.?? for S.? that I did not catch when I did the massive replace a few weeks ago.
After this commit, we only have about 8 compiler warnings left. But I'd like to rebase this pull request after we build 2.5-M1 (unless anybody thinks we need it before)