Include original message when wrapping exceptions, for more helpful client error messages
Make sure skeletons are not overwritting cached files.

Skeleton files were being written even when a cached file was left alone.
Fix indentation.
Merge pull request #10 from zanata/skeleton-fix

Make sure skeletons are not overwritting cached files.
Merge pull request #4 from zanata/better-exception-messages

Include original message when wrapping exceptions, for more helpful clie...