Make examples consistently use 4-space indentation.

Make examples consistently use 4-space indentation.

Use \file{} for file names.

Prefer \code{blat} and \emph{blat} to {\tt blat} and {\em blat}; this matches
current style in the Library Reference a bit better.

Made the example startup banner current.  The version number should be
bumped before the next release.