Update dependencies

Merge pull request golang-migrate#114 from albenik/master

github.com/docker/docker package updated to api v1.37

Run `go mod tidy`

Docker builds need to use dep to manage dependencies

Remove support for Go modules

Update commented out imports to use v3

Use Go 1.11 (with modules enabled on alpine linux 3.8) for docker builds

Support Go 1.11 and drop support for Go 1.9

    - Support modules in Go 1.11

Merge branch 'update_pkgs'

Disable CGO to build binaries statically on the building platform

    - Previously, only cross-compiled binaries were built statically
    - Addresses: golang-migrate#45