add brew section to osx page and move away comments obsoleted by this change

doc/install/OSX.mdwn

@@ -1,3 +1,14 @@
+## using Brew
+
+<pre>
+sudo brew update
+sudo brew install haskell-platform git ossp-uuid md5sha1sum coreutils pcre
+cabal update
+cabal install git-annex --bindir=$HOME/bin
+</pre>
+
+## using MacPorts
+
 Install the Haskell Platform from [[http://hackage.haskell.org/platform/mac.html]].
 The version provided by Macports is too old to work with current versions of git-annex.
 Then execute
@@ -11,6 +22,8 @@ sudo cabal update
 cabal install git-annex --bindir=$HOME/bin
 </pre>
 
+## PATH setup
+
 Do not forget to add to your PATH variable your ~/bin folder. In your .bashrc, for example:
 <pre>
 PATH=~/bin:/usr/bin/local:$PATH

doc/install/OSX/comment_2_25552ff2942048fafe97d653757f1ad6._comment

@@ -4,4 +4,5 @@
  date="2012-07-24T15:09:29Z"
  content="""
 I've moved some outdated comments about installing on OSX to [[old_comments]].
+And also moved away some comments that helped build the instructions above.
 """]]

doc/install/OSX/comment_4_d513e21512a9b207983d38abf348d00f._comment

@@ -1,16 +0,0 @@
-[[!comment format=mdwn
- username="https://www.google.com/accounts/o8/id?id=AItOawm_-2XlXNyd6cCLI4n_jaBNqVUOWwJquko"
- nickname="David"
- subject="installing via homebrew"
- date="2012-09-05T11:11:55Z"
- content="""
-I had to:
-
-    cabal update
-
-before:
-
-    cabal install git-annex
-
-
-"""]]