Set minimum maven version to 3.0.4 and updated plugin versions
added mockito-core to base pom
fixed scala warnings
moved import to a language compiler option so that scala 2.9 continues to work
Clean imports
Attribution. Closes #689
Merge branch 'update-plugin-versions' of github.com:nhajratw/cucumber-jvm into nhajratw-update-plugin-versions
Attribution. Closes #691