Finish runtime caching, begin runtime json errors

completes [67856314]
starts [#67314208]

https://www.pivotaltracker.com/story/show/67314208
https://www.pivotaltracker.com/story/show/67856314

Activities can by_pass the runtime json conversion w/ prevent_conversion

This is handy when being copied, or when running certain tests.

TODO: Maybe also specify a way to prevent running conversions using ENV
for testing scenarios?

whitespace cleanup.

This method was moved to sg_permissions.

Test for error detection in converter.

Invalidate chache when name or author_name changes.