More VL server backend stuff

Quicklisp:
  - Add wrapper for html-template quicklisp library

VL server:
  - Incorporate html-template library to allow for includes and
    variables in .html and .css files
  - Create common header file, split out stylesheet stuff from html
    files
stupid xdoc tweak which, I think, fixes #290.
Get 'make clean' to additionally delete some of the files reported in #305