Refactor vm executeWithContext method slightly
Refactor vm executeWithContext method slightly

Creating a slice in a few places just to evaluate a single node seemed
like overkill. Being able to take in a variable number of nodes to execute
at a single time feels much nicer.

rajthilakmca/grubby,slawosz/grubby,grubby/grubby,rajthilakmca/grubby,slawosz/grubby,rajthilakmca/grubby,grubby/grubby,kachick/grubby,kachick/grubby,grubby/grubby,kachick/grubby,slawosz/grubby