Workflow Asset updates, classification result loading

New

.tar.gz
assets now have their contents automatically indexed. Contents can now be viewed from the app.onecodex.com/workflows/assets page.
Assets API moved out of experimental status: the Assets API is now generally available and no longer requires the
X-OneCodex-Api-Experimental
header.

Improved

Classification results should now load with reduced timeouts.
Asset deletion now includes more validation to prevent deletion of assets in use by analysis jobs.