Don't devtools-install Zelig if (production)
Don't devtools-install Zelig if (production)

Moved the install_github("IQSS/Zelig") line under an "if (!production)" statement. 
In prod. environment, Zelig install should be done outside of the rook scripts/rApache.
We've seen some trouble with devtools not being able to download the master zip file from github; 
but the following appears to work: 

unzip master.zip
R
> library(devtools)
> install("Zelig-master")
vjdorazio/TwoRavens,vjdorazio/TwoRavens,vjdorazio/TwoRavens,vjdorazio/TwoRavens,vjdorazio/TwoRavens