#304 Improving Dynlimit setting

[Lucario]

Currently the dynlimit setting only allows coowners+ by default to toggle it on and off. To improve this feature, users could be allowed to control more aspects of it. On GameSurge, the floating limit is the no. of current users +15. Users should be allowed to set their own margin for the floating limit for greater flexibility e.g. current no. of users +5 to +10 or +2 to +20 etc. They should also be allowed to control the time period before ChanServ resets the chhannel limit.