version 0.3.3
- Further fix when using tibble or other data.frame format that
requires using 
drop = TRUE when subsetting columns 
version 0.3.2
Bugfixes
- Fixed bug in add_covariate
 
version 0.3.1
Bugfixes
- Fixed conflict with sf packages and class ‘dist’ when calculating
covariates
 
NEWS.md setup
- added NEWS.md creation with newsmd