Merge pull request #52
Fix exception string format
Expose retry functionality through GalaxyInstance
Unit tests for GET retry feature
Rephrase misleading documentation on GET retries
Merge pull request #53 from crs4/master

Expose retry functionality through GalaxyInstance
Fix handling responses without body

When a request isn't successful the response doesn't (may not?) contain
a body.  The previous code caused an AttributeError in such cases by
accessing the 'body' attribute even in such cases.  This commit fixes
the issue by accessing the 'content' attribute.

It also changes the logic to only log the response's content at the
debug level.
galaxy: added first stub of oo interface
galaxy.objects: extended Workflow
galaxy.objects: more wrappers
added objects/galaxy_instance.py
galaxy objects: added delete_library and library test
galaxy objects: added delete_workflow
galaxy objects: create_library: added description and synopsis
galaxy objects: simplified error generation
galaxy objects: delete methods now have no return value
galaxy objects: more error checking
galaxy objects: added create/delete_history
galaxy objects: added upload_file_contents
galaxy objects: cleaned up error checking