And also to GetBlockRange. This requires an updated version of zcashd
`getblock` RPC that returns these values. These values are written to
the compact block cache (/var/lib/lightwalletd/db/main/blocks), but of
course older cached compact blocks won't have these values. To get these
values into all cached blocks, shut down lightwalletd, remove that file,
and restart (with, of course, an updated version of zcashd running).
- improved corruption recovery (don't back up by just 1 block at a time)
- move darksidewallet gRPCs to their own .proto file
- this force-push removes my commits for reorg testing using SetState