Rename asset routes test to public routes.

 On branch master

	renamed:    test/webserver/asset_routes_test.js -> test/webserver/public_routes_test.js
Improve devserver test to handle errors.

 On branch master

	modified:   test/commands/devserver_test.js
Update Enginemill core to read webapp configs.

 On branch master

	modified:   enginemill.js
	modified:   lib/commands/devserver.js
	modified:   lib/commands/webserver.js
	modified:   lib/utils.js
	modified:   lib/webserver/app.js
	modified:   lib/webserver/index.js
Serving static assets from theme directory.

 On branch master

	new file:   lib/webserver/controllers/theme.js
	modified:   lib/webserver/routes/routes.js
	new file:   test/fixtures/webapps/default/application.ini
	new file:   test/fixtures/webapps/default/themes/mountains/images/mindblown.gif
	new file:   test/fixtures/webapps/default/themes/mountains/scripts/widget.js
	new file:   test/fixtures/webapps/default/themes/mountains/stylesheets/main.css
	new file:   test/webserver/theme_routes_test.js