url = <url>
requested URL. The url can include list of parameters, which are
parsed before the url is fetched. Parameters are :
%s next word from the SMS message, starting with the second one
(i.e., the first word, the keyword, is not included); problematic
characters for URLs are encoded (e.g., '+' becomes '%2B')
%S same as %s, but '*' is converted to '~' (useful when user enter
a URL) and URL encoding isn't done (all others do URL encode)
%r words not yet used by %s; e.g., if the message is "FOO BAR FOOBAR
BAZ", and the has been one %s, %r will mean "FOOBAR BAZ".
%a all words of the SMS message, including the first one.
%t the time the message was sent, formatted as "YYYY-MM-DD HH:MM",
e.g. "1999-09-21 14:18"
%p the phone number of the sender of the SMS message
%P the phone number of the receiver of the SMS message
%q like %p, but a leading '00' is replaced with '+'
%Q like %P, but a leading '00' is replaced with '+'