Merge pull request #117 from Tahiraj/development

Fixes and Enhancements to Crosstabs
ANOVA (added error message zero residual SS)

fixes #43
ANOVA (added error message inf values dep. var.)

fixes #114
ANOVA (added error message negative weights)

fixes #108
ANOVA (added basic plot function)

I started working on a function that makes profile plots in JASP for
the ANOVA function. However, because ggplot2 is not yet supported by
JASP, I commented out the function
Merge pull request #118 from raviselker/development

ANOVA fixes
ANOVA (added error message infinite weights)
Merge pull request #119 from raviselker/development

ANOVA (added error message infinite weights)