Fix build error message "Bad option: ';_;'."

* jshint option ';_;' removed from JS files.
* Add target "distclean" to Makefile, which will also wipe locally
  installed node modules.
* Add target "install-local-node-modules" to Makefile, which will
  install all required node modules (with correct version, this should
  fix the recess issues in newer recess versions).
* You can now run "make use_global_node_modules=1" to use globally
  installed node modules, instead of ones installed in "node_modules/".