Feature/groovy templates performance

"play precompile" is very slow on big projects. The problem is in method `GroovyTemplateCompiler.source` that performs genormous amount of `String.replaceAll` operations. Removing every `String.replaceAll` helped to boost performance. Our applications work fine with play-1.3.x.

http://play.lighthouseapp.com/projects/57987-play-framework/tickets/1873-boost-groovytemplatecompiler-performance