README: point to Documentation/SubmittingPatches

It was indeed not obvious for new contributors to find this document in
the source tree, since there were no reference to it outside the
Documentation/ directory.

Signed-off-by: Matthieu Moy <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: moy

README

@@ -42,10 +42,12 @@ including full documentation and Git related tools.
 
 The user discussion and development of Git take place on the Git
 mailing list -- everyone is welcome to post bug reports, feature
-requests, comments and patches to [email protected]. To subscribe
-to the list, send an email with just "subscribe git" in the body to
-[email protected]. The mailing list archives are available at
-http://marc.theaimsgroup.com/?l=git and other archival sites.
+requests, comments and patches to [email protected] (read
+Documentation/SubmittingPatches for instructions on patch submission).
+To subscribe to the list, send an email with just "subscribe git" in
+the body to [email protected]. The mailing list archives are
+available at http://marc.theaimsgroup.com/?l=git and other archival
+sites.
 
 The messages titled "A note from the maintainer", "What's in
 git.git (stable)" and "What's cooking in git.git (topics)" and