Add 'dump' and 'import' commands to tcbmgr
tcbmgr: Sync DB before closing after import
BUG tcbmgr: Fix write_all
tcbmgr: Handle some of the review comments

See: https://github.com/Incubaid/tokyocabinet/commit/aa94cc6968d51c57fe62e2f2f449d1020497c05c
Merge branch 'dump_import' into arakoon

* dump_import:
  tcbmgr: Handle some of the review comments
  BUG tcbmgr: Fix write_all
  tcbmgr: Sync DB before closing after import
  Add 'dump' and 'import' commands to tcbmgr