add plugin (3g-modem-manager)

[vuplus_dvbapp] / lib / python / Plugins / SystemPlugins / 3GModemManager / apnlist.xml

<apns version="6">
  <apn carrier="SKT3G" mcc="450" mnc="05" apn="web.sktelecom.com" mmsc="http://omms.nate.com:9082/oma_mms" mmsproxy="smart.nate.com" mmsport="9093" type="default,supl,mms" />
  <apn carrier="KT-HSDPA" mcc="450" mnc="08" apn="alwayson-r6.ktfwing.com" mmsc="http://mmsc.ktfwing.com:9082" type="default,supl,mms" />
</apns>