Update to lastest stable Git that does not warn about repo-config

Using QGit 2.3 with Git >= 1.7.5 is annoying because it always displays a
warning at startup.

component/git/buildout.cfg

@@ -13,8 +13,8 @@ parts =
 
 [git]
 recipe = hexagonit.recipe.cmmi
-url = http://kernel.org/pub/software/scm/git/git-1.7.3.4.tar.bz2
-md5sum = 3a2602016f98c529cda7b9fad1a6e216
+url = http://kernel.org/pub/software/scm/git/git-1.7.4.5.tar.bz2
+md5sum = 2fa6c4c847ed87523cf55de54af457eb
 configure-options =
   --with-curl=${curl:location}
   --with-openssl=${openssl:location}