Provide more error information if available
[fixes #715] Make server in blueprint optional
reduce CPU + save battery by using https://github.com/krisselden/broccoli-sane-watcher for detecting changes.
temp fix for broccoli-sane-watcher
[fixes #888] ensure live reload port isn’t printed if its not used.
Merge pull request #875 from wagenet/better-errors

Provide more error information if available
add warning if trying to glob in app.import