Convenience functions for calculating BC-SMDs

This version includes several new convenience functions for pre-processing data and calculating between-case effect size estimates. It also includes updates to the built-in web app, as well as a few small bug fixes.

• New convenience functions:
  • Added a convenience function calc_BCSMD() for pre-processing data, fitting an lme() model, and calculating g_mlm() all in one go.
  • Added a convenience function default_times() for calculating default time-points for multiple baseline designs.
  • Added batch_calc_BCSMD() function for calculating BC-SMD effect size estimates for multiple studies of the same design.
• Changes to the shiny app:
  • Fixed bug in shiny app that occurred when uploading a multiple baseline design or a treatment reversal design.
  • Updated the layout of model output in the shiny app so that it is easier to read.
  • Added rclipboard package to the installation instruction of the shiny app.
  • Added Bryant et al. (2018) and Thiemann & Goldstein (2001) to the references in the shiny app.
  • Updated the study design labels in example datasets for multiple baselines across participants.
• Changes to example datasets:
  • Added the academic response outcome data from Lambert et al. (2006) to the package and the shiny app.
  • Updated the Bryant et al. (2018) dataset using the group instead of school as the cluster variable.