add message about actual value when assertion failed for: isEqualToComparingFieldByField, isEqualToIgnoringGivenFields, isEqualToIgnoringNullFields, isEqualToComparingOnlyGivenFields
Merge pull request #146 from michal-lipski/issue134

#134 add message about actual value when assertion failed
minor refactoring
Issue #148 - Bytes assertions enhancements - compact message for better readability
Issue #148 - Standard Java, Binary and Hexadecimal representation of objects