largefiles: use "ui.configlist()" to get largefiles.patterns configuration stable

largefiles: use "ui.configlist()" to get largefiles.patterns configuration

current lfconvert implementation uses combination of "ui.config()" and
"str.split(' ')" to get largefiles.patterns configuration.

but it can not handle multiline configuration in hgrc files correctly.

lfconvert should use "ui.configlist()" instead of it, as same as
override_add does.

--- a/hgext/largefiles/lfcommands.py	Wed Nov 23 16:25:44 2011 -0600
+++ b/hgext/largefiles/lfcommands.py	Thu Nov 24 17:54:50 2011 +0900
@@ -71,9 +71,7 @@
             lfiles = set()
             normalfiles = set()
             if not pats:
-                pats = ui.config(lfutil.longname, 'patterns', default=())
-                if pats:
-                    pats = pats.split(' ')
+                pats = ui.configlist(lfutil.longname, 'patterns', default=[])
             if pats:
                 matcher = match_.match(rsrc.root, '', list(pats))
             else:

--- a/tests/test-lfconvert.t	Wed Nov 23 16:25:44 2011 -0600
+++ b/tests/test-lfconvert.t	Thu Nov 24 17:54:50 2011 +0900
@@ -5,7 +5,8 @@
   > graphlog =
   > [largefiles]
   > minsize = 0.5
-  > patterns = **.dat
+  > patterns = **.other
+  >     **.dat
   > EOF
 
 "lfconvert" works