MEDIUM: h1: enlarge the scope of accepted version chars with accept-invalid-http...

MEDIUM: h1: enlarge the scope of accepted version chars with accept-invalid-http-request

We used to support both RTSP and HTTP protocol version names with and
without accept-invalid-http-request, but since this is based on the
characters themselves, any protocol made of chars {0-9/.HPRST} was
possible and not others. Now that such non-standard protocols are
restricted to accept-invalid-http-request, there's no reason for not
allowing other letters. With this patch, characters {0-9./A-Z} are
permitted when the option is set.