changed location type to option
use defaults from Flyway instead of Option type where possible
override sbt configuration with system properties and refactoring
Merge branch 'master' of github.com:flyway/flyway
add sbt plugin largetest
Merge branch 'master' of github.com:flyway/flyway
remove Option types and update to sbt 0.13.1
Merge pull request #662 from cdedie/master

improves sbt-plugin (less Option types, command line override, large-test)