convert: workaround for cvsps.cache under Windows
In non-cygwin environment, cvsps fails to create its cache directory and redirect its output to stderr. Just ignore the error and capture stderr as well.
#header#
<title>Mercurial repositories index</title>
</head>
<body>
<h2>Mercurial Repositories</h2>
The specified repository "#repo|escape#" is unknown, sorry.
Please go back to the main repository list page.
#footer#