Updated Plugin descriptor;

Author: mansiarora

src/main/groovy/ExcelExportGrailsPlugin.groovy

@@ -1,4 +1,6 @@
-class ExcelExportGrailsPlugin {
+import grails.plugins.Plugin
+
+class ExcelExportGrailsPlugin extends Plugin {
     // the plugin version
     def version = "1.0.0"
     // the version or versions of Grails the plugin is designed for