Some changes in ECPolynomialField

Christian: I was was not able to compile your commit. I did some
changes in the generics to make it run on my machine.
Minor bug in RSASignature test file
System.out in test file removed
Generalized Converters
Converter
Merge branch 'master' of https://github.com/bfh-evg/unicrypt

Conflicts:

src/main/java/ch/bfh/unicrypt/math/algebra/dualistic/classes/BinaryPolyn
omialField.java

src/main/java/ch/bfh/unicrypt/math/algebra/dualistic/classes/PolynomialF
ield.java