I notice the plugin settings tab was not loading the
existing plugin settings from the settings file.
It was properly writting to the file, but not reloading
on initialization.
added a loadValue() function so PluginSettings can call when the
pluginService is injected. Added isLoading state flag to prevent
the onItemsChanged from saving back settings when loading is happening.
Added null wise checks for properties that may be not ready yet
when loading.
bbedward