scide: dumpOSC: actually call the signal when the wiget is toggled
class library: server: keep dump osc mode over reboots
Before this commit, the dump mode of the server would be reset on reboot. The purpose of the server class is however to keep settings also over reboots, if possible. For instance if the server was muted, it will be muted also after a reboot. So here the same is applied to whether the server dumps osc or not. In debugging sessions, where one is likely to dump osc messages, one is also likely to reboot the server. This also makes the ide display consistent.