Bootstrap-ify LESS and CSS

I've refactored the LESS/CSS so it closely matches Bootstrap.

- Core classes are now named `tm-tag` (previously `myTag`) and `tm-input` (previously `myTagManager`)
- Add support for Bootstrap like semantic color and size classes
- Bootstrap-style remove icon (× character instead of x)
- Update JS file to match new names
- Remove &nbsp; chars from inside tag, and replace with remove icon margin
- Better usage of LESS variables
- Regenerate CSS from LESS

![tag-styles](https://f.cloud.github.com/assets/27655/520826/d6aa924e-bf4a-11e2-94b5-33d3340801ac.png)

In addition, I've added the ability to interpolate the tag class from the input class, for example <input class='tm-input tm-input-success'/> will cause all tags to have class `tm-tag-success`.

Note that the base color of tags is now gray, in keeping with Bootstrap standards.