Added branch-specific info to README.

Author: paulp

README.rst

@@ -1,3 +1,10 @@
+################################################################################
+                              NOTICE
+################################################################################
+
+The legacy/msil branch records the state of master at the point when
+msil was removed.  It is not under active development.
+
 ################################################################################
                               THE SCALA REPOSITORY
 ################################################################################
@@ -7,11 +14,11 @@ and how to build it. For information about Scala as a language, you can visit
 the web site http://www.scala-lang.org/
 
 Part I. The repository layout
---------------------------------------------------------------------------------                            
+--------------------------------------------------------------------------------
 
 Follows the file layout of the Scala repository. Files marked with a † are not
 part of the repository but are either automatically generated by the
-build script or user-created if needed.  This is not a complete listing. :: 
+build script or user-created if needed.  This is not a complete listing. ::
   scala/
    +--build/                    Build products output directory for ant.
    +--build.xml                 The main Ant build script.
@@ -111,12 +118,12 @@ Part III. Common use-cases
 
 - ``ln -s build/quick/bin qbin`` (once):
 - ``ant && qbin/scalac -d sandbox sandbox/test.scala && qbin/scala -cp sandbox Test``
-  
+
   Incrementally builds quick, and then uses it to compile and run the file
   ``sandbox/test.scala``. This is a typical debug cycle.
 
 - ``ant replacelocker``
-  
+
   "unfreezes" locker by updating it to match the current source code.
 
   - This will delete quick so as not to mix classes compiled with different
@@ -137,7 +144,7 @@ Part III. Common use-cases
     ANT_OPTS="-Xms512M -Xmx2048M -Xss1M -XX:MaxPermSize=128M" ant docs
 
 - ``ant dist``
-  
+
   Builds a distribution.
 
   - Rebuilds locker from scratch (to make sure it bootstraps).