Better grouping.
Better grouping.

- group $sl filtering and validation.

- this commit might change replies sent to clients,
	since the validation check is done eaerlier now,
	and we might return S_MISSING_PARAM before S_BAD_OTP for example.

- this should really not cause any issues though,
	the order of which error is raised first should not matter to clients.

ahojjati/yubikey-val,Yubico/yubikey-val,Yubico/yubikey-val,Yubico/yubikey-val,ahojjati/yubikey-val,ahojjati/yubikey-val