Ability to hide undefined results in verbose viewer

[bloodmc]

Description

While verbose undefined results are useful in showing a denied permission, it can sometimes cause information to be hard to find when a plugin like GriefDefender performs many lookups against persistent and transient data in a short period of time.

Proposed Behaviour

I propose one of the following options to improve this behaviour at least for my plugin

1. Add a tickbox on the verbose viewer to hide undefined results
2. Add a parameter to the verbose command to not include undefined results

Extra Details

No response

[Rasgnarok]

Following

[Turbotailz]

Added in #392