Add autoreplace macros to chat

Add the ability to configure lists of keyword/replacement pairs.

When a keyword is entered in a chat input bar either at the beginning of a line or preceded by any non-word character (the definition of a "word" character depends on the chosen language), and is followed by a space (' ') character, the keyword is removed from the chat input bar and replaced with the configured replacement. Replacement can be prevented for an entered keyword by following it with a non-breaking space character (alt-space on Mac or Linux, control-space on Windows).

If the same keyword appears in more than one list, the one in the highest list in the preference order is used.

A list may be exported to an xml file, and then imported from that file.