Add methodParams attribute for Parameters

This PR is about adding the ability to pass parameters to "parameters providing method" in the @Parameters annotation's `method` attribute.

This is just my quick hack, so it's ok if you feel that this is too hackish or that this doesn't comply to unit testing standard. This works in mine, so I would like to try my luck to see whether you like this idea also =)
I think it's better if the documentation should also mention that the methods referred to in `method` attribute should accept a single `Object[]` argument when you want to use `methodParams` attribute. Will update tomorrow.