Pull-merge request to update the maven-groovy-spock-archetype for updated groovy-all, and maven build plugins

Fixes and upgrades a couple of archetype pom definitions. Specifically,

1.    groovy.version property is updated to 1.8.5
2.    added project.build.sourceEncoding default property as 'utf-8'
3.    maven-compiler-plugin is upgraded to 3.1
4.    maven-surefire-plugin is upgraded to 2.14.1
5.    added includes for **/*Test.groovy and **/*Spec.groovy sources in maven-surefire-plugin configuration