Some bug fixes and refcounter-based prep stmts cleanup
- introduce show global_prepared_statements command (#1524)
- ref counters for global pstmts map (#1515)
- use xxh64 instead of murmur (#1510)
- add portal tacking on client side (#1494)
- fix proctitle display (#1520)
- remove penalty yield and cond pending to fix od_assert(server != NULL) crash
- introduce od_assert
- fix epoll event loss (#1499)
- do not reset servers in pipeline mode (#1483)
- fix scram auth with plain password on both sides (#1493)
- fix duplex deadlock with read_ready optimization (#1475)
Full Changelog: v1.5.2-rc1...v1.5.2-rc2