Fix memory leak when using hg commands over http repositories
When using hg commands over an http repository in a long running process, a
httphandler instance is leaked for each command, because of a loop
handler.parent -> OpenerDirector and OpenerDirector.handlers -> handler which
is not handled by Python's gc. Discussion on #mercurial concluded that removing
the __del__ method solved the problem.
{header}
<title>Mercurial repository not found</title>
</head>
<body>
<h2>Mercurial repository not found</h2>
The specified repository "{repo|escape}" is unknown, sorry.
Please go back to the <a href="{url}">main repository list page</a>.
{footer}