Full unicode autodetection, minor kannel updates, typo in play theme

Updated javascript, counting sms characters, to set "unicode" checkbox automatically if text contains non-latin characters and automatically unset if no unicode characters used. So user cant set it manually and option to set checkbox by default is useless.

Updated kannel gateway functions:
Double check if unicode message is going with correct coding&charset
Add playsms username to kannel in "account" parameter for billing.
Correct dcs field computation by not sending mclass for non-flash messages

Fixed typo in page_login of play theme.