graphmod: rename graph-topological config to graph-group-branches

The latter suggests what the change is slightly better.

mercurial/graphmod.py

@@ -227,10 +227,10 def dagwalker(repo, revs):
     lowestrev = revs.min()
     gpcache = {}
 
-    if repo.ui.configbool('experimental', 'graph-topological', False):
+    if repo.ui.configbool('experimental', 'graph-group-branches', False):
         firstbranch = ()
-        firstbranchrevset = repo.ui.config('experimental',
-                                           'graph-topological.firstbranch', '')
+        firstbranchrevset = repo.ui.config(
+            'experimental', 'graph-group-branches.firstbranch', '')
         if firstbranchrevset:
             firstbranch = repo.revs(firstbranchrevset)
         parentrevs = repo.changelog.parentrevs

tests/test-glog-topological.t

@@ -40,7 +40,7 later.
 
 (display all nodes)
 
-  $ hg --config experimental.graph-topological=1 log -G
+  $ hg --config experimental.graph-group-branches=1 log -G
   o  8
   |
   o  3
@@ -62,7 +62,7 later.
 
 (revset skipping nodes)
 
-  $ hg --config experimental.graph-topological=1 log -G --rev 'not (2+6)'
+  $ hg --config experimental.graph-group-branches=1 log -G --rev 'not (2+6)'
   o  8
   |
   o  3
@@ -80,7 +80,7 later.
 
 (begin) from the other branch
 
-  $ hg --config experimental.graph-topological=1 --config experimental.graph-topological.firstbranch=5 log -G
+  $ hg --config experimental.graph-group-branches=1 --config experimental.graph-group-branches.firstbranch=5 log -G
   o  7
   |
   o  6