Mostly some pedantic changes such that `make clean' always ignores
errors. Also changed the top clean target to do the `touch
configs/current' dance instead of realclean.
Many of the directories in progs/ were missing .gitignore files or
were tracking generated files. This patch is basically the process of
running `make' in each directory and then finding the untracked files
with `git-ls-files -o --exclude-per-directory=.gitignore'. The existing
files were also sorted.
