Add the license for mush. This is the relevant section taken from

the README file in the mush distribution.

1 files changed, 21 insertions, 0 deletions

diff --git a/licenses/mush-license b/licenses/mush-license
new file mode 100644
index 00000000000..f8f3dedabfe
--- /dev/null
+++ b/licenses/mush-license
@@ -0,0 +1,21 @@
+Mush is copyright (c) 1986, 1987, 1988, 1989, 1990, 1991 by Dan Heller.
+All Rights Reserved.   This software is not in the public domain.
+
+Redistribution of the unmodified source code is permitted as long as all
+copyright notices remain intact and all other identifying notices remain
+in the code and in the binary.  This includes message headers on outgoing
+mail and the startup message.  Future releases may extract the release
+version from the message headers of mush-originated messages to aid in
+implementing features and providing backwards compatibility with previous
+versions.  Modification of the source for personal use is permitted.
+Modifications sent to the authors are humbly accepted and it is their
+prerogative to make the mods official.  Only the "official" sources may be
+redistributed and no sale of the code or any part thereof is permitted
+without written consent from the authors.  Further, no part of the code
+may be used in any other product, free or otherwise, without consent from
+the authors.  Distribution of sources containing adaptations of the SunView
+interface to XView or to any X11-based interface is expressly prohibited.
+
+MUSH IS PROVIDED AS IS, WITHOUT WARRANTY.  AUTHORS HEREBY DISCLAIM
+ALL WARRANTIES INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES
+OF FITNESS FOR A PARTICULAR PURPOSE.