Wip/h3nk3 enable monitoring

Sorry for this huge PR! It brings the partner monitoring into Activator. There are still a couple of fixes that are needed to not be a regression from the previous version, but this will work as a starting ground. 

Most of the functionality has been copied from the 1.2-branch. What has been changed is that this version uses sbt files for the configuration of the monitoring tools (rather than straight injection of parameters into the forked process). There are also two plugins that are used in collaboration with sbt-rc and sbt-play-plugin, namely sbt-ad and sbt-nr.