Create static directory for static assets.

Setting the foundation for reducing GET's.  Plan is to create a
shell script that puts separate JavaScript files together, minifies,
then changes file name to include the MD5 sum, and finally updates
the properties file to point to this generated file name.  This
will we can use expires = never for asset's in the static directory.

Having one directory where we know all these assets live simplifies the logic
a bit.
Base functions needed to banish scroll bars.

I love the bespoke (slide-show) UI.  Simple one-message pages, and using arrow
keys (or swipe on mobile) to move quickly from page to page.

To implement this, we need to know:

  1. how big our available canvas is, and

  2. how much space each part of our content requires.

With these two measures we can figure out where to split the content
so each "chunk" fits on one page (canvas).  This code provides
functions that answer these two questions.