Makefile / build process needs improvement / cleanup

[tmcintos]

The Makefile is "quick and dirty" and I do not have much time to invest in fixing it.

Referring to the latest version (presently on the wozniac-1 branch):

Issues:

• Build of optimized version of PDF manual is currently not reproducible. The Ghostscript "-c" option (intended to remove timestamps and document ID) does not appear to be having the desired effect.
• Ghostscript optimization options were suggested by GPT and have not been fully vetted. This was the only combination I found that produced a significantly smaller file without loss of quality vs the original.
• Dependencies for krusader.pdf are incomplete (e.g. Memory.pdf is not called out).
• Running ./mkgitinfo.sh as part of the PDF build may not be the best approach.
• clean target is a mess.
• List of dependencies in comments is out of date.