Update README with submodule build info

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

README

@@ -8,19 +8,35 @@ builtin cache to decrease server io-pressure.
 
 Installation
 
-  $ make gitsrc=<path>
+  $ make
   $ su
-  $ make prefix=<path> install
+  $ make install
 
+This will install cgit.cgi and cgit.css into "/var/www/htdocs/cgit".
 
-Default value for gitsrc is "../git", and this directory should contain the
-git sources.
+Note: The initial "make" will create a submodule 'git' and clone the git
+repository at git://git.kernel.org/pub/scm/git/git.git in it. If you
+already have a local git git repository that you want to use as origin
+for the submodule, run
 
-Default value for prefix is "/var/www/htdocs/cgit". This directory will 
-contain "cgit.cgi" and "cgit.css" after 'make install'.
+  $ git clone -s <path-to-git-repo> git
+  $ ./submodules.sh -u
 
-After installation, httpd.conf probably must be updated with a Directory-
-section for cgit, possibly something like this:
+before running "make".
+
+
+Dependencies
+
+  -git (1.5.2-rc0 or newer, due to git submodule) installed
+  -zip lib
+  -crypto lib
+  -openssl lib
+
+
+Apache configuration
+
+A new Directory-section must probably be added for cgit, possibly something
+like this:
 
   <Directory "/var/www/htdocs/cgit/">
       AllowOverride None
@@ -53,3 +69,13 @@ throughput over page freshness.
 
 The generated content contains the complete response to the client, including
 the http-headers "Modified" and "Expires".
+
+
+The mis(sing) features
+
+Submodule links in the directory listing page have a fixed format per
+repository. This should probably be extended to a generic map between
+submodule path and url.
+
+
+The end.