add offline license key

ss042c.rst

@@ -10,4 +10,16 @@ SpreadServe 0.4.2c notes
   matching the one in ``sseng.ini:OWNER``.
 * Port 80 or 8090: RealTimeWebServer defaults to 8090. If you stay with this default you should fix ``%SSROOT%\cfg\dns_host_name.txt``
   to be ``myhostname:8090``. If you want to run on port 80 make sure no other process like IIS is on 80, that you're running
-  with high enough rights to bind to port 80, and that you fix ``%SSROOT%\cfg\webcfg.py:RTWSPort=80``.
+  with high enough rights to bind to port 80, and that you fix ``%SSROOT%\cfg\webcfg.py:RTWSPort=80``.
+
+**Offline license key**
+
+Firewall rules may prevent your SpreadServe install phoning home on port 80 to spreadserve.com. Or you may want to
+avoid sharing any information about commercially sensitive spreadsheets. In those cases you'll need an offline license
+key, which is free during the SpreadServe beta. The key below is good for any host until 2017-07-31. Past it into
+``%SSROOT%\cfg\license.txt``.
+
+c3ByZWFkc2VydmUuY29tOjgwLDIwMTcwNzMxLG9mZmxpbmUsRkEtQjEtRUQtREUtQ0EtREUs
+MzYyQTYwRkY3RERCMTlBRTQxQkVBRjUyNTZGOTlGQjYyQjlCRUY4NEE0NDM0QTc3QjcyQTMw
+QzQ4RUREOUM2NDUzNEMyMDE1ODBGRDM5OTU3NjVGMjUwMzM4RUM4NzM0QTY2RUZEOTEwMTAz
+REFGQTU5MzczRTc1RjEyRjIyNjY=