Added plugin for snyk

Author: bhermann

project/plugins.sbt

@@ -5,3 +5,6 @@ addSbtPlugin("com.typesafe.sbt" % "sbt-native-packager" % "1.3.2")
 // coverage
 addSbtPlugin("org.scoverage" % "sbt-scoverage" % "1.5.1")
 addSbtPlugin("com.codacy" % "sbt-codacy-coverage" % "1.3.12")
+
+// preparation for dependency checking
+addSbtPlugin("net.virtual-void" % "sbt-dependency-graph" % "0.9.1")