GA release v1.0.44

Changes since 1.0.42: v1.0.42...v1.0.44

Notable:

• --postpone-cut-over-flag-file implies touching indicated file
• support for PK column UPDATE (fixes #519)
• Implement teardown (#479 ), now gh-ost can be embedded as a library -- thanks @nikhilmat !
• Allow gh-ost to modify the server using extra port (#491 ) -- thanks @zmoazeni !
• Doc updates -- thanks @druud !
• Remove plaintext password from log
• Building via go1.9

$ sha256 *
583eb9fe9055b422521a7a60083860248bf5a52226dceb561cb60d8520bfecc0  gh-ost-binary-linux-20180211093207.tar.gz
6940fde2720179f4b3c4c74b906e746060b18a0a1e3229dcf818cd944a57dfd7  gh-ost-binary-osx-20180211093207.tar.gz