 calculates a p value for a test of the null hypothesis
\(H_0: \psi \neq \psi_0\) for the two sided case,
\(H_0: \psi \leq \psi_0\) for the case <code>alternative = "greater"</code>, and
\(H_0: \psi \geq \psi_0\) for the case <code>alternative = "less"</code>.
We make no assumptions and do not rely on large sample approximations.
It also optionally constructs a \(1 - \alpha\) percent confidence interval for \(\psi\).
The computation is somewhat involved so it is best for small sample sizes. The
calculation 