[FIX] ir.module.module: install_from_urls is restricted to administrators and only accept urls from apps server
[FIX] ir.module.module: download() method is now a no-op. This method was in fact already a no-op as the "url" field is never set explicitly in the code.
[FIX] tools.email_split: improve email extraction using stdlib + extra tests

The original code was having issues telling apart
names containing emails from the actual email.
This patch is inspired by Etienne Hirt's patch
on bug 1165531 for OpenERP 6.1.
This will also help solve bug 1199386, if we can
centralize all email parsing through this helper.