Remove deprecated UnsafeSlice and use unsafe.Slice
Stabilize the behaviour of Prev when the cursor already points to the first element - Fix Cursor.Prev() out of range issues in v1.3.9 - Relates to boltdb/bolt/issues/357 (Cursor inconsistent when mixing cursor.Delete() with Put() in same transaction)
full diff: https://github.com/etcd-io/bbolt/compare/v1.3.9...v1.3.10