Update icons, metadata, version strings.  Add 'volo version' command.
Restyle toolbar; restructure LESS compilation.

We compile app.less directly, referencing the bootstrap .less files,
so we can inherit/extend bootstrap without explicitly putting bootstrap
classes in our HTML.
Filter out unnecessary files from the appcache. (Also update volo-appcache.)
Fix block [[Image]] tags with embedded newline (in [[Star]] article).
Inline .mw files for static pages into the source code.