Changes
- #87: core/state: fix storageChange.copy() dropping origvalue
- #89: core/types: return error instead of panic on invalid signature length
- #90: core/txpool: fix list.Add() totalcost overflow
- #91: triedb/pathdb: fix journal RLP nil/empty-slice conflation
- #94: fix(tracers): honor trace_timeout in traceBlock loops (PLT-986)