We rely on the include path to find many of these headers. It
especially doesn't make sense to use #include "foo.h" for headers
in the top-level include directory.
It was already unsigned in sudoers but not in the front-end or the
python plugin. Making this consistent resolves a lot of -Wconversion
warnings. Also clean up some other -Wconversion warnings in sudo_debug.c.
Previously we needed to include headers required by the various
sudo*h files. Now those files are more self-sufficient and we
should only include headers needed by code in the various .c files.
