POSIXify ./configure, and comment some parts of it.
Thanks to Martin GUY for pointing out that ./configure was not POSIXly correct.

/trunk/configure | 51 35 16 0 +++++++++++++++++++++++++++++++++++----------------
1 file changed, 35 insertions(+), 16 deletions(-)

# Overall toolchain configuration: paths, jobs, etc...

menu "Paths and misc options"

source "config/global/ct-behave.in"

source "config/global/download_extract.in"

source "config/global/build-behave.in"

source "config/global/paths.in"

source "config/global/logging.in"

endmenu