imageoverlay: Change CvSeq by GSList
imageoverlay: Change CvSeq by GSList

Change-Id: I48ccecf8b15fe6971f2ad9e6b297d7b7011b636f

Kurento/kms-core,TribeMedia/kms-core,TribeMedia/kms-core,ESTOS/kms-core,shelsonjava/kms-core,Kurento/kms-core,shelsonjava/kms-core,KurentoLegacy/gst-kurento-plugins,shelsonjava/kms-core,KurentoLegacy/gst-kurento-plugins,ESTOS/kms-core,KurentoLegacy/gst-kurento-plugins,ESTOS/kms-core,ESTOS/kms-core,TribeMedia/kms-core,Kurento/kms-core,TribeMedia/kms-core,Kurento/kms-core,shelsonjava/kms-core,KurentoLegacy/gst-kurento-plugins