merge achievements from development to master. (#21)

[ZsBT]

• Issue #13: A MrzParserException is thrown when the dates in the MRZ are invalid (e.g 1999 September 35) (#14)

• • No MrzParserException thrown when the dates in the MRZ are invalid.

• New boolean isValidDate in the MrzDate that indicates the validity of the date.

• • Documentation added for the isValidDate() function of the MrzDate class

• Unit tests fix

• JDK version downgraded to 1.7 for Android compatibility

• set validDateOfBirth and validExpirationDate booleans to false when date are invalid

• introducing development branch

• Error handling when unparseable dates (#17)

• No MrzParseException

• Unparseable year, month or day set to -1

• Raw value field in MrzDate (#19)

this will merely help an auto-correction in the future.