mq: ban \r and \n in patch names (issue4711)

This is at best crazy, and at worst will break things like the series
file. Let's just stop the madness.

hgext/mq.py

@@ -1102,7 +1102,7 b' class queue(object):'
             if name.startswith(prefix):
                 raise util.Abort(_('patch name cannot begin with "%s"')
                                  % prefix)
-        for c in ('#', ':'):
+        for c in ('#', ':', '\r', '\n'):
             if c in name:
                 raise util.Abort(_('%r cannot be used in the name of a patch')
                                  % c)

tests/test-mq-qnew.t

@@ -21,6 +21,7 b''
   >     hg qnew .mqfoo
   >     hg qnew 'foo#bar'
   >     hg qnew 'foo:bar'
+  >     hg qnew "`echo foo; echo bar`"
   > 
   >     hg qinit -c
   > 
@@ -110,6 +111,7 b' plain headers'
   abort: patch name cannot begin with ".mq"
   abort: '#' cannot be used in the name of a patch
   abort: ':' cannot be used in the name of a patch
+  abort: '\n' cannot be used in the name of a patch
   % qnew with name containing slash
   abort: path ends in directory separator: foo/ (glob)
   abort: "foo" already exists as a directory
@@ -178,6 +180,7 b' hg headers'
   abort: patch name cannot begin with ".mq"
   abort: '#' cannot be used in the name of a patch
   abort: ':' cannot be used in the name of a patch
+  abort: '\n' cannot be used in the name of a patch
   % qnew with name containing slash
   abort: path ends in directory separator: foo/ (glob)
   abort: "foo" already exists as a directory