[PATCH] Added validity setting within OISD module

Hi,

I added implementation of missing features in gw/smsc/smsc_oisd.c.
Now driver set Validity Period field from msg->sms.validity,
or validityperiod directive from config file, or set to 24 hours.

Patches are here:
http://bugs.kannel.org/view_bug_page.php?f_id=0000124

please vote and commit.

best regards,
Dariusz Markowicz