Merge branch 'postgres-lock-fix'

Addresses: golang-migrate#4

Fix cli builds

    - Removed sqlite3 support from binaries
        - It was never working anyways: mattes/migrate#244
    - Don't use cgo as is requires a cross-compiler to build for other platforms
        - cgo was originally added for this reason: mattes/migrate#238 (comment)

Merge pull request golang-migrate#231 from mattes/cli-updates

build cli with all source and database drivers

Merge pull request golang-migrate#216 from thingful/v1.3.1-neo4j-https

Register neo4j driver using a pseudo `neo4js` protocol scheme.

update readme

Update version.go

remove cleanpath, fix mysql ensureVersionTable

add example dockerfile

allow to force NilVersion

add NewWithDatabaseInstance example