Add missing SecondsEmpty param parsing and request.

[Senaris]

Based on query command 'channellist': /// Query info: /// Usage: channellist [-topic] [-flags] [-voice] [-limits] [-icon] [-secondsempty] /// /// Displays a list of channels created on a virtual server including their ID, /// order, name, etc. The output can be modified using several command options. /// /// Example: /// channellist -topic /// cid=15 pid=0 channel_order=0 channel_name=Default\sChannel /// channel_topic=No\s[b]topic[\/b] total_clients=2|cid=16 ... /// error id=0 msg=ok

Added a new option 'includeEmpty' in the GetChannel command. Added a new parameter 'ChannelEmptyDuration' as timespan to parse this option.

Basic description:

• seconds_empty it's a param which starts counting on the server side from the moment when the channel gets empty.

Example:

• If i'm on channel xaxa[id 123], seconds_empty it's -1
• If i leave the channel, seconds_empty starts counting in seconds since the last time someone was on the channel.