CryptoUtils refactorization 

- Improved exception handling. Some exceptions are now thrown instead or being ignored.
- Non-private CryptoUtils methods are now synchronized, because Cipher and other objects are shared and this would break if different threads would run some methods at the same time.
- Fatal exceptions in the initialization of the CryptoUtils are now thrown as RuntimeExceptions. This might get replaced with an own RuntimeException later.

I used Eclipse auto format in the CryptoUtils class, because I created this class and always used auto format. I didn't date to auto format other classes, although they are formatted pretty weird.