#78 Prettifier injected as a service

I was trying to inject filter into directives without much luck. I
introduced another layer of abstraction by creating a service, which is
injected into filter or directives. This seems to be doing fine.
Corrected log message and level
Restored class comparison for conditional

At one point, I had changed the class identification from equals
function on the class object to string comparison of the class names.
This later broke the code when the class was defined as a nested class.
Restoring the class object comparison for dependency inspector. I
believe other generated factory classes still use class object
comparison anyway, so, there is no need to go through the other
templates.
Module.run implementation - first cut