Extended text filter functionality to allow precise filtering of speech, Razor overhead messages and sys messages
Right now the text filter option under Filters -> Text & Messages only filters speech.
With this PR, players would be able to decide where the text should be filtered on:
- Speech
- Overhead messages from Razor
- System messages
For system messages, they can additionally decide if the filtered messages should still trigger overhead messages and be found via the "insysmsg" script expression.
The change is backwards compatible so players using the speech filter already won't notice any changes.

I'm finished with the implementation now. Debugged and tested it as much as I could on Outlands and had no more issues.
It also fixed a previous bug where overhead messages would not be registered if the sys message was filtered by the "filter repeated system messages" option.
The new edit form for filter options is still a bit choppy, it looks good in the designer but not when I run it. But that's just aesthetics.