Replacement text cannot be longer than 255 characters

As a note, to enable this.

One needs to alter the {wordfilter} table. The replacement field needs to be altered. I changed the replacement column from a varchar(255) to mediumtext.
varchar can hold a maximum of 255 characters. mediumtext can hold a maximum of 16777215 characters (according to some reading).

Then, one has to allow the add and edit word forms to allow more than 255 characters.

On lines 475 & 535, I changed
'#maxlength' => 255,
to
'#maxlength' => 16777215,

This would probably be better served up as a patch, but everything seems to work now.