Clean ununsed options properties and classes.

bigbluebutton-client/resources/config.xml.template

...luebutton/main/model/modules/BigBlueButtonModuleLoader.as

.../org/bigbluebutton/main/model/modules/ModuleDescriptor.as

...igbluebutton/main/model/options/BrowserVersionsOptions.as

...c/org/bigbluebutton/main/model/options/SkinningOptions.as

...org/bigbluebutton/modules/caption/model/CaptionOptions.as