update citation.R with tweaks for INLA and epiR
Update citation.R with tweaks for INLA and epic in alphabetical order
Update citation.R with tweaks for INLA and epic in alphabetical order

Hopefully with the commas in the right place this time, my bads.
Merge pull request #684 from duncandoo/patch-1

update citation.R with tweaks for INLA and epiR