Updates to Gulp task structure and code cleanup.

Cleaning up Gulp tasks and adding an easier way to config paths in task files. Also removing Bower directory from `/public` and moving back into `app`, while only pulling out the minified bower files and putting those in the `dist` within `/public`; allows for a cleaner `/public` directory.

@DFurnes 

On local development, SSH'ed into Vagrant site directory, run:

`````
npm install
bower install
`````

CC: @angaither @barryclark