implement faux-stereo pan and misc polishing/bugfixes for feature #25

* reverted local channels implicit addition/removal via config tree state
* added LinJam::ComputeFauxStereoPan() method
* added LinJam::GetMonoPairSourceN() and LinJam::GetStereoPairSourceN() methods
* added CONFIG_TYPES dictionary and LinJamConfig::restoreVarTypeInfo() method
* added LinJamConfig::makeHostId() method
* added LinJamConfig::addChannel() method
* added LinJamConfig::destroyChannel() method
* added LinJamConfig::setRemoteStereo() method
* added LinJamConfig::trimStereoName() and LinJamConfig::setStereo() methods
* added LinJamConfig::getUserMasterChannel() method
* added LinJamConfig::getChannelByName() method
* removed Channels::broughtToFront() method