Rules should be able to be marked as in audit mode

[sporkmonger]

A rule in audit mode will still execute and the results of that execution would be logged, but it would not be incorporated into the actual decision being made for a request. The associated trace should indicate that the trace belongs to a rule in audit mode.

[sporkmonger]

Testing for this feature should include running two copies of the same plugin with different configuration, one in audit mode, one in normal mode.