Support for Java 14 Records

[mbechto]

It would be nice to be able to use this library with Java 14 records, for example:

public record LineRecord(
    @FixedField(offset = 1, length = 42)
    String firstStr,
    @FixedField(offset = 43, length = 5)
    String secondStr
) {}

As it is a lot more declarative than defining traditional POJOs & it automatically implements toString, hashCode and equals.