only compile parser files if necessary
only compile parser files if necessary

clean task deletes old java parser classes, in order to regenerate them when necessary

sunny256/crate,gmrodrigues/crate,puneetjaiswal/crate,aslanbekirov/crate,aslanbekirov/crate,EvilMcJerkface/crate,sunny256/crate,aslanbekirov/crate,husky-koglhof/crate,crate/crate,husky-koglhof/crate,puneetjaiswal/crate,EvilMcJerkface/crate,husky-koglhof/crate,adrpar/crate,gmrodrigues/crate,puneetjaiswal/crate,adrpar/crate,sunny256/crate,EvilMcJerkface/crate,crate/crate,adrpar/crate,gmrodrigues/crate,crate/crate