This "Java / AngularJS" webapp uses an embedded Jetty container, as is described in Maven + Jetty = Quick WebService and http://www.jamesward.com/2011/08/23/war-less-java-web-apps.
Build the project with
$ mvn install
You will need to set the REPO environment variable, so the execution wrapper script knows where to find the maven dependencies. For example:
$ export REPO=$HOME/.m2/repository
Now you can run your webapp with:
$ sh target/bin/webapp
(the wrapper script is not executable by default).
When developing in IDEA it is very useful to make Jetty run in hot swap mode so that you instantly see the result of source changes in the resulting web page. The setup for this is described here https://gist.github.com/naaman/1053217.
(IDEA LiveEdit pluging)[http://plugins.jetbrains.com/plugin/?id=7007] + (JetBrains IDE Support plugin for Chrome) [https://chrome.google.com/webstore/detail/jetbrains-ide-support/hmhgeddbohgjknpmjagkdomcpobmllji] is a very powerful combination for developing HTML/JavaScript.