Change configuration options and tasks that use underscores to camelCase

Fixes #39 . **Must be reviewed/merged after #63 as it was branched off of that initiative.**

## Problem

Some of the tasks, filenames, and configuration options in wGulp inconsistently use underscores and camelCase.  This makes it hard for consumers to keep track of configuration options and task names.

## Solution

Switch uses of underscores to use camelCase.

This aligns with @shanesizer-wf 's motto of "The name is the name is the name."

## Testing (How to +10)
- Tests should pass
- Examples should still work
- Try it in at least one wGulp project
- Attempt to find any underscores I may have missed

@trentgrover-wf 
@shanesizer-wf 
@evanweible-wf