Changed GHOP module imports to be consistent with rest of Melange code. The imports used the from <module-path> import <module> as <local_module_name> syntax. These kinds of imports are changed to import <module_path.module_name> syntax to be consistent with the Melange code base. Reviewed by: Lennard de Rijk

from django.dispatch import Signal

request_started = Signal()
request_finished = Signal()
got_request_exception = Signal(providing_args=["request"])