Putting more thought into the build process

Removed 3rd-party JS libs from the repository, switching JS package management over to Bower.

To install bower and pull down the latest version of the dependencies:

```bash
npm install -g bower
bower install
```

I added a makefile to combine all of the dependency management into a single (two, actually) command:

```bash
make install dependencies
```

The above pulls down all the dependencies from Composer, npm, and Bower. (This is also a bit cleaner when written out in documentation, as three commands have been merged into just the one.)

Let me know what we think of this.