deployment repo not cleaned before update

Created by: clarsonneur

When an update is executed but fails for some reason, forjj has not did a git add to those files. So, then, next time, the plugin won't detect any change reported to forjj and then forjj will never execute a git add of those files updated.

The workaround is to checkout those files and restart forjj process.

But forjj shoud clean the deployment repo before, so files updated during a forjj update will be reported to forjj.