doc/, and now www/ trees, but only using the "cvsup" transport.
When "make update" is run using a tree's makefile, it can also use
"cvs" (except for www/) and "svn" (only src/).
Clean up documentation and code regarding "make update":
- Increase oddness by adding support for WWWSUPFILE and NO_WWWUPDATE to
Makefile.inc1 (analogous to PORTSSUPFILE/NO_PORTSUPDATE and
DOCSUPFILE/NO_DOCUPDATE; WWWSUPFILE already supported by www/Makefile).
- Document all trees that support CVS_UPDATE.
- Document all trees that support SUP_UPDATE.
- Document SVN_UPDATE.
- Document NO_WWWUPDATE.
- make.conf(5) mistakenly said that *SUPFILE* had defaults.
- Add an example entry for WWWSUPFILE.
69c488cdc6