Fix several small issues

This block of changes fixes a few problems:

* Bake templates use new style placeholders #4321
* Http\Client responses now automatically unzip gzipped responses #4280
* Fixed a missing RouteCollection property.
* Fixed issues when generating the context for a stack trace contained an object that raised an exception while converting an object into a string with `__debugInfo()`.
I do this all the time. Too my python brain damage.