Create entry processor package

Fix for jsr107 tck 26: move all EntryProcessors into org.jsr107.tck.entryprocessor and make Serializable to support distributed environments.

Merged with upstream changes before requesting pull request.

Did make one fix in RI.  In RICache.invoke(), had to be sure not to wrap CacheException multiple times.
Will try to make a pull request for that also.