simstudy 0.8.1

New features

• Added the ability to generate data from an empirical distribution by using new functions genDataDensity and addDataDensity.
• The binary and binomial distributions can now accommodate a "log" link.

Minor fix

• addCorGen no longer requires all clusters to have the same size when using the rho and corstr arguments to define the correlation.
• Fixed an issue that prevented functions defined outside the global namespace from being referenced in defData.