Shell of theme cloned from bitweaver/theme_bootstrap
Add a simple preview until a proper one can be generated
Create a location to start building the replacement icon set. icon-map.txt
contains a list of required icons and this will be updated with the name the
selected desktop standard one so we can build new icons sets.
It may be prudent to add a mapping function so that the existing standard
libraries can just be used, but that requires a bit more work and simply copying
a set will get me started.