Skip compilation when skip scoverage

Author: Justin Jia

src/main/java/org/scoverage/plugin/SCoveragePreCompileMojo.java

@@ -219,6 +219,9 @@ public void execute() throws MojoExecutionException
 
  Properties projectProperties = project.getProperties();
 
+ // for maven-compiler-plugin (compile), scala-maven-plugin (ompile)
+ setProperty( projectProperties, "maven.main.skip", "true" );
+
  // for maven-resources-plugin (testResources), maven-compiler-plugin (testCompile),
  // sbt-compiler-maven-plugin (testCompile), scala-maven-plugin (testCompile),
  // maven-surefire-plugin and scalatest-maven-plugin