user-manual: move howto/using-topic-branches into manual

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 7e41ca6a0d3e4329d1efc10b4dcb90613975e5bd..a7daa08731715846d68b35c4e9da740e878ed05a 100644 (file)
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -490,7 +490,7 @@ merge.summary::
 merge.tool::
        Controls which merge resolution program is used by
        gitlink:git-mergetool[l].  Valid values are: "kdiff3", "tkdiff",
-       "meld", "xxdiff", "emerge", "vimdiff"
+       "meld", "xxdiff", "emerge", "vimdiff", and "opendiff"
 
 merge.verbosity::
        Controls the amount of output shown by the recursive merge