intellij-cucumber-scala-0.3.4

• Upgrade to IntelliJ 2016.1 (build 145.258+)
• Upgrade to intellij-scala-plugin 3.0.0 (scala 2.11.6)

intellij-cucumber-scala-0.3.3

• Upgrade to IntelliJ 15.0.2 (build 143.1184+)
• Upgrade to intellij-scala-plugin 2.0.4 (scala 2.11.4)
• Support inheriting step definitions from traits (#16)