CHANGES for BAS 0.3

- fixed EB.global function to include prior probabilities on models

- fixed update function 

CHANGES for BAS 0.2

- fixed predict.bma to allow newdata to be a matrix or vector with the
  column of ones for teh intercept optionally included.

- fixed help file for predict 

- added modelprior argument to bas.lm so that users may now use the
  beta-binomial prior distribution on model size in addition to the
  default uniform distribution

- added functions uniform(), beta-binomial() and Bernoulli() to create
  model prior objects

- added a vector of user specified initial probabilities as an option for
  argument initprobs in bas.lm and removed the separate argument user.prob