Add support for excluding packages and files

Author: Hani Suleiman

src/main/groovy/org/scoverage/ScoverageExtension.groovy

@@ -24,6 +24,10 @@ class ScoverageExtension {
     File sources
     /** range positioning for highlighting */
     boolean highlighting = true
+    /** regex of excluded packages, separated by colons */
+    String excludedPackages = ""
+    /** regex of excluded files, separated by colons */
+    String excludedFiles = ""
 
     ScoverageExtension(Project project) {
 
@@ -85,7 +89,8 @@ class ScoverageExtension {
                     plugin.addAll(parameters)
                 }
                 plugin.add("-P:scoverage:dataDir:${extension.dataDir.absolutePath}".toString())
-                plugin.add('-P:scoverage:excludedPackages:')
+                plugin.add("-P:scoverage:excludedPackages:${extension.excludedPackages}")
+                plugin.add("-P:scoverage:excludedFiles:${extension.excludedFiles}")
                 if (extension.highlighting) {
                     plugin.add('-Yrangepos')
                 }