Added indexOf(VEnum enum) formula function that returns enum.getIndex()
IndexOf formula: adding a simple unit test

Signed-off-by: Kunal Shroff <shroffk@bnl.gov>
Merge pull request #1 from shroffk/master-tonlyttt

IndexOf formula: adding a simple unit test
Merge pull request #1 from tonlyttt/master

Test is there, merging. Will also need to to create a function set appropriate for these kinds of functions, but will keep as it is in the meantime.