Examples:
list($err, $res) = $api->upload_media('image', '/data/img/fighting.jpg');
list($err, $res) = $api->upload_media('voice', '/data/img/song.amr');
list($err, $res) = $api->upload_media('video', '/data/img/go.mp4');
list($err, $res) = $api->upload_media('thumb', '/data/img/sky.jpg');
Result:
[
null,
{
type: "image",
media_id: "CVS_UPz62LKIfDwc7bUWtI250x_KBLhOuYgkHr1GjVxJCP8N9rOYfgIKXSY5Wg9n",
created_at: 1439623233
}
]