Add fundamental R naming conventions

[aridyckovsky]

Is your feature request related to a problem? Please describe.
There is a large distribution of naming conventions used in R, but need to move toward best practices and lower variance of convention use. See: Bååth - 2012 - The State of Naming Conventions in R.pdf.

Describe the solution you'd like

• Contant names
• Parameter names
• Function names
• Package namespaces
• File names
• Cite and link to the source PDF