added waterDeity.m

[ kappaOut, kappaCollect ] = waterDeity( dataMatrix, nIterations) runs
a total of nIterations kappa analyses on (incomplete) input dataMatrix.

- kappaOut contains the mean kappa over all iterations.
- kappaCollect contains all separate kappa values (column 1) and their
corresponding p values (column 2).
Added kappa to statisticAnalysis.m