Add recovery_persist & recovery_refresh

One time executables. recovery_refresh can be used at any time to
ensure recovery logs in pmsg are re-placed at the end of the FIFO.
recovery_persist takes the recovery logs in pmsg and drops them
into /data/misc/recovery/ directory.

Bug: 27176738
Change-Id: Ife3cf323930fb7a6a5d1704667961f9d42bfc5ac