New help file for initial force subscription

lang/en/help/forum/subscription2.html

@@ -0,0 +1,32 @@
+<P ALIGN=CENTER><B>Forum Subscription</B></P>
+
+<P>When a person is subscribed to a forum it means that 
+they will be sent email copies of every post in that forum
+(posts are sent about <?PHP echo $CFG->maxeditingtime/60 ?> minutes 
+after the post was first written).
+</P>
+
+<P>People can usually choose whether or not they want to be 
+subscribed to each forum.
+</P>
+
+<P>However, if you choose to force subscription on a particular forum 
+then all course users will be subscribed automatically, even those that
+enrol at a later time.
+</P>
+
+<P>This is especially useful in the News forum and in forums
+towards the beginning of the course (before everyone has 
+worked out that they can subscribe to these emails themselves).
+</P>
+
+<p>If you choose the option "Yes, initially" then all current and future
+course users will be subscribed initially but
+they can unsubscribe themselves at any time. If you choose "Yes, forever"
+then they will not be able to unsubscribe themselves.
+</p>
+
+<p>Note that changing later from "Yes, initially" to "No" will not unsubscribe
+existing users, it will only affect future course users.
+</p>
+