added textFieldBackgroundColor view property
added textFieldBackgroundColor view property

umhan35/react-native-search-bar,iDay/react-native-search-bar,zedman/react-native-search-bar,Olegas/react-native-search-bar,umhan35/react-native-search-bar,samsel/react-native-search-bar,jtthrillson/react-native-search-bar,umhan35/react-native-search-bar