PP3 -- Celestial Charts Generator Code

Updated years in copyright notice.

Added label for sigma Oct.

Many changes due to new Texinfo version.

Changed Aquarius link to Scorpius.

Finished LaTeX hooks section. First complete version of the manual. Minor
improvements.

Corrected a couple of mistakes.

Final touches before first public announcement.

Added list of constellations. Added a couple of index entries. Changed tag
line. Minor improvements.

Described user defined preamble line by line. Began with section about hooks.

betelg image added.