OPENDJ-1602 (CR-5566) New pluggable storage based backend


BackendImpl.java:
Renamed update() to write() as per the PoC.
Made all SPI interfaces public.

EntryContainer.java:
Consequence of renaming BackendImpl.update().

JECompressedSchema.java:
Added import for ByteString + used correct API
Removed JE imports.

git-svn-id: https://svn.forgerock.org/opendj/branches/opendj3-server-dev@11444 41b1ffd8-f28e-4786-ab96-9950f0a78031