[pom] Drop support for maven 3.1.1 - now require 3.2.5 (jdk 6)
[pom] Drop support for maven 3.1.1 - now require 3.2.5 (jdk 6)

hazendaz/spotbugs-maven-plugin,hazendaz/spotbugs-maven-plugin,hazendaz/spotbugs-maven-plugin