Small fixes/cleanup

- Renamed StylizedButton and StylizedEditText to StyledButton and StyledEditText to be consistent
- Colsolodated the constructors for all of the Styled* classes to ease maintenance
- Changed instances where instances of WikipediaApp were used to access static class methods
- Simplified an instance where a boolean return value was checked before returning it to simple return the result of the function call itself

Change-Id: Ie10a13897a147d34cef5ab76d0839aba3b20d1ff