instaweb: use 'browser.<tool>.path' config option if it's set.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Acked-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/config.txt

@@ -369,7 +369,8 @@ branch.<name>.rebase::
 
 browser.<tool>.path::
 	Override the path for the given tool that may be used to
-	browse HTML help. See '-w' option in linkgit:git-help[1].
+	browse HTML help (see '-w' option in linkgit:git-help[1]) or a
+	working repository in gitweb (see linkgit:git-instaweb[1]).
 
 clean.requireForce::
 	A boolean to make git-clean do nothing unless given -f

git-instaweb.sh

@@ -274,6 +274,14 @@ webrick)
 	;;
 esac
 
+init_browser_path() {
+	browser_path="`git config browser.$1.path`"
+	test -z "$browser_path" && browser_path="$1"
+}
+
 start_httpd
 url=http://127.0.0.1:$port
-test -n "$browser" && "$browser" $url || echo $url
+test -n "$browser" && {
+	init_browser_path "$browser"
+	"$browser_path" $url
+} || echo $url