Rename no-icons style to mimic base bootstrap naming, plus add a no responsive, no icons variant. 

This is a post-2.3.0 follow-up to #96.

There are two files that include Bootstrap files w/ icons: 
- bootstrap.min.css (no responsive styles, with icons)
- bootstrap-combined.min.css (with responsive styles, with icons).

Historically, there's also been one file that excluded icons (useful for using Font Awesome):
- bootstrap.no-icons.min.css (with responsive styles, with icons).

These commits adjust that second set (those without icons) to the following which more closely mimics the naming of the base files (those with icons):
- bootstrap.no-icons.min.css (no responsive styles, no icons)
- bootstrap-combined.no-icons.min.css (with responsive styles, no icons).

The commits don't make it totally clear how but this was accomplished by moving bootstrap.no-icons.min.css to bootstrap-combined.no-icons.min.css, then adding a version from getbootstrap.com with no responsive styles and no icons.

Also included is a change to index.html to match (adjusting the no-icons variants to use the -combined version to match the label (responsive + no icons).