Fix copy-&-paste errors in command line interface.

bin/dulwich

@@ -218,15 +218,18 @@ def cmd_diff_tree(args):
 
 def cmd_rev_list(args):
     opts, args = getopt(args, "", [])
-    if len(args) < 2:
-        print "Usage: dulwich tag NAME"
+    if len(args) < 1:
+        print 'Usage: dulwich rev-list COMMITID...'
         sys.exit(1)
-    porcelain.tag(".", args[0])
+    porcelain.rev_list('.', args)
 
 
 def cmd_tag(args):
-    opts, args = getopt(args, "", [])
-    porcelain.tag(".", args[0])
+    opts, args = getopt(args, '', [])
+    if len(args) < 2:
+        print 'Usage: dulwich tag NAME'
+        sys.exit(1)
+    porcelain.tag('.', args[0])
 
 
 def cmd_reset(args):
@@ -238,7 +241,7 @@ def cmd_reset(args):
         mode = "soft"
     elif "--mixed" in opts:
         mode = "mixed"
-    porcelain.tag(".", mode=mode, *args)
+    porcelain.reset('.', mode=mode, *args)
 
 
 commands = {