Use plurals for valid/invalid input get in InputFilterInterface

[Maks3w]

InputFilterInterface::getValidInput():array and InputFilterInterface::getInvalidInput():array should be InputFilterInterface::getValidInputs():array and InputFilterInterface::getInvalidInputs():array

Both method return always a collection type (array)

[jeanCarloMachado]

I made a pull request for it: #98

[weierophinney]

This repository has been closed and moved to laminas/laminas-inputfilter; a new issue has been opened at laminas/laminas-inputfilter#13.