Update migration docs

Correct and clarify information around empty migrations
Addresses: golang-migrate#244

Merge pull request golang-migrate#227 from zhevron/mssql-params

Fix incorrect syntax errors for MSSQL driver

Update dependencies to resolve: golang-migrate#202

Update packages that depend on the wrong golint import path

Addresses: golang-migrate#202

Use alpine 3.9 for building Docker images

Merge pull request golang-migrate#167 from arpando/fix/DocumentNilError

Fix document nil error

Merge pull request golang-migrate#150 from tsenart/atomic-migrations-…

…table-creation

postgres: Make `ensureVersionTable` atomic

Run `go mod tidy`

Fix broken build

    - `gem install` no longer recognizes the `--no-ri` and `--no-rdoc` options. Use `--no-document` instead.
    - References:
        - ruby/rubygems#2354
        - rubygems/bundler#6624

Merge pull request golang-migrate#145 from bobrovde/fix-clickhouse

Changed clickhouse migrations table struct