Merge pull request #27 from onyx-peekaboo/master

Optimize the page selection dialog focus
clean code
change OnyxSysCenter.getDictionaryList() -> OnyxSysCenter.getAvailableDictionaryList()
add IReaderMenuHandler.showSpacingSettings()
OnyxAndroidSDK:根据是否支持行距，隐藏显示相对应的菜单