Two new functions

So I got tempted to make this work ... and it promptly failed on me via devtools (happy to share the log).   I ended up adding two functions to a) add via apt-get and b) add via R's install packages. With that I got to a green travis shield.  

I don't claim that these two versions are final but maybe you want to review and take parts or all of them while we both to complete the feature set?