DDMsgReader: Speed improvements and updates for newscans, and updates for the indexed newscan menu mode.

DDMsgReader: Speed improvements and updates for newscans, and updates for the indexed newscan menu mode. Possible speed improvement when loading messages (When calling get_all_msg_headers(), passing false now for getting vote headers most of the time). New: User setting to only show new messages in a newscan (defaults to true/enabled) In the message list, there is now an additional space before the 'from' name, in case one of the status characters is a letter (this should look better). New: In lightbar mode, the indexed newscan menu can optionally 'snap' to the next sub-board with new messages when showing/returning to the menu Fix: When listing personal email, messages to the user were written with the to-user color wuen unread. Now the regular colors are always used (since all of a user's personal emails are 'to' them). Fix: For indexed newscan, if there are no sub-boards selected for scan in the user's newscan configuration, then output a message and exit. Otherwise, it would end up in an infinite loop. Updated how user settings are loaded, to ensure that default user settings from DDMsgReader.cfg actually get set properly in the user settings.