Stars display incorrectly for glm and lm models

[jknowles]

In the apsrtable function I incorrectly overwrote the Pr(>|t|) column in the coefficient summaries for lm and glm objects in an attempt to overwrite it for any models that don't automatically generate on the fly t-tests of model parameters for the purposes of statistical significance.

I have fixed this now, and both merMod and glm and lm models should be working as expected in my jknowles/apsrtable@dev branch.