Issue 78

* unrelated javadoc updates in metadata parser
* added 'rest' to root error context to make clear which instance of command is used (where multiple exist with same simple name)
* updated error creation on generic failure to include full stack trace as message
All the other methods doesnt seem to use the logger, we may need this (tracing a bug, which in the current state we would just have the last message, an a couple of nested exceptions could have occurred ). I comment just this line but the same concept apply to all methods (and maybe other places as well I think). Below I comment an usage of the logger (which I was expecting)