#237 fix wrong calculation of the selectedPage
#237 fix wrong calculation of the selectedPage

franvera/react-native-scrollable-tab-view,skv-headless/react-native-scrollable-tab-view,iancanderson/react-native-scrollable-tab-view,skv-headless/react-native-scrollable-tab-view,skv-headless/react-native-scrollable-tab-view