Getting you up to speed w/ the grunt workflow and other changes, plus organization

I hope you don't mind, but I took what you had done and organized it a bit better. Here's what I did.

1. Pulled the latest from v2.0 branch (you were quite behind, I've made a lot of changes in the last week)
1. Changed the option name `target` to `insertTarget`. I was afraid people might be confused that this was a target other than the selector used when applying the method.
1. Changed the default value of `insertLocation` from `this` to `this.selector`. `this` is a jQuery object in this instance, and since we're wrapping it below w/ the variable, I wanted to keep this clean.
1. Updated `location` to `insertLocation`. I want to be sure people understand this location is relative to the `insertTarget` set above.
1. Update jQuery object variable from `$target` to `$insertTarget` to match the new option naming.
1. Updated the condition for the `insertTarget` to be a bit cleaner. Because we need the method to be able to be strung along w/ other methods, we don't want to `return false;` here. Instead I set a nested condition with it's own error logging and fired the `swapLoadingClass` to update the `body` class.

Let me know if any of this is confusing. I know a lot has changed in the last week, unfortunately you picked the exact weekend I had planned on doing this work to add the target option. I've been wanting to upgrade the core of the plugin and switch to a Grunt workflow for a while, and this was the first chance I've had. For some good resources on getting started with Grunt, check this comment https://github.com/jimmynotjim/scrollNav/pull/25#issuecomment-25855931.