calcHypotheses: calculate hypotheses
In spiders: Fits Predator Preferences Model

calculates hypotheses, given a user specifed null and alternative

1	calcHypotheses(hyp, Xdst, Ydst, J, I, balanced, EM, em_maxiter)

`hyp`	a 2-tuple specifying the null and alternative hypotheses, respectively
`Xdst`	matrix of sums of number of eaten prey species s during occurrence t; rows indexed by time, and cols indexed by prey species, TxS
`Ydst`	matrix sum of number of caught prey species s during occurrence t; rows indexed by time, and cols indexed by prey species, TxS
`J`	vector of predators caught in each time period
`I`	vector of number of days all traps were left out in a given time period
`balanced`	boolean specifying balanced data or not
`EM`	boolean specifying if EM algorithm should be used
`em_maxiter`	maximum number of iterations allowed for EM algorithm