Mdbx devel 5 (#1413)

Makefile

cmd/integration/commands/flags.go

cmd/integration/commands/refetence_db.go

cmd/integration/commands/stages.go

core/blockchain_insert.go

core/chain_makers.go

eth/downloader/downloader.go

eth/gasprice/gasprice_test.go

eth/stagedsync/stage_hashstate.go

eth/stagedsync/stage_headers.go

ethdb/kv_lmdb.go

ethdb/kv_mdbx.go

ethdb/mdbx/dist/CMakeLists.txt

ethdb/mdbx/dist/ChangeLog.md

ethdb/mdbx/dist/README.md

ethdb/mdbx/dist/VERSION

ethdb/mdbx/dist/mdbx.c

ethdb/mdbx/dist/mdbx.c++

ethdb/mdbx/dist/mdbx.h

ethdb/mdbx/dist/mdbx_chk.c