em bin command update

 On branch master

	modified:   bin/em.js
	renamed:    lib/webserver/business/content_render_engine.js -> lib/content_render_engine.js
Better error reporting in devserver and webserver

 On branch master

	modified:   lib/commands/devserver.js
	modified:   lib/commands/webserver.js
Refactor most webserver components

 On branch master

	modified:   lib/content_render_engine.js
	new file:   lib/template_engine.js
	modified:   lib/webserver/controllers/content.js
	modified:   lib/webserver/index.js
	new file:   lib/webserver/responders/html_responder.js
	new file:   lib/webserver/responders/text_responder.js
	modified:   lib/webserver/response.js
	new file:   lib/webserver/response_context.js
	modified:   package.json
	new file:   test/fixtures/webapps/default/content/index.md
	new file:   test/fixtures/webapps/default/themes/mountains/templates/home/index.html
	new file:   test/fixtures/webapps/default/themes/mountains/templates/layouts/base.html
	new file:   test/webserver/content_routes_test.js