Add comments to Makefile

Makefile

@@ -1,3 +1,33 @@
+# /opt/ghc/Makefile: convenient for building binary GHC distributions
+# AUTHOR: Sean Leather
+# LICENSE: public domain
+
+################################################################################
+# To use this Makefile, I do the following:
+#
+#   1. Create a directory for version $V of the GHC distribution.
+#
+#        $ pwd
+#        /opt/ghc
+#        $ mkdir -p $V/src
+#
+#   2. Create a symbolic link to this Makefile
+#
+#        $ cd $V
+#	 $ ln -s ../Makefile
+#
+#   3. Download and unpack the desired GHC distribution
+#
+#	 $ cd src
+#	 $ wget http://www.haskell.org/ghc/dist/$V/ghc-$V-i386-unknown-linux-n.tar.bz2
+#	 $ tar jxf ghc-$V-i386-unknown-linux-n.tar.bz2
+#
+#   4. Install (or clean)
+#
+#	 $ cd ..
+#	 $ make install
+#
+
 VERSION  := ${shell basename `pwd`}
 PREFIX   := ${shell pwd}
 SRCDIR   := ./src/ghc-${VERSION}