Add FixedMessage to all filters

Merge all changes from ChatModerator/fixed-fix

Update all filters to the new FixedMessage format

Add initial spec for the FixedMessage object

Fix NPE on matcher instantiation in several filters

`fixed` parameter seems to be broken?

Standardize Pattern variable and method name

Update to work with the new FixedMessages

Fixed matching on original message in all filters

Closes OvercastNetwork/ChatModerator#7