WIP: Implemented support for multi-line message writing in message entry
In the message entry box just single-line messages could be written; now it is possible to insert multi-line messages by typing Ctrl-Enter; the message is still sent by just pressing Enter. To get this feature, it was necessary to change the widget to a GtkEntry to a GtkTextArea, so some parts of the code were modify to satisfy API differences.
Attempts to fix #154 (closed)
Edited by Daniel Garcia Moreno