Fixed keystore pass in NbmTask.
Minor refactoring.
OpenIDE-Module-Requires now has an explicit support.
Removed trailing spaces from build.gradle.
Added EvaluateUtils.asPath.
Added NbmKeyStoreDef.
Added EvaluateUtils.asString
Refactored NbmPluginExtension.
NbmPlugin now applies the java plugin.
Add test for plugin signing. No implementation yet.
Merge commit '09ff76a743f178ea3f83710088ab743cefa72827' into signing

Merges fixes in signing and rewrite of plugin extension class from Groovy to Java.
Fix tests and samples.
Use Gradle 1.12.