Don't check in autogenerated automake files...

This mostly reverts commit cffa25bf219401512c457a64b48dbe47aa7ceda2.
In retrospect, better to not check in auto-generated automake files into git.
Will need to add a proper 'make dist' target to make a distributable tarball
with these files so that running bootstrap.sh is not necessary.
merge ns-portability: new files dir
merge ns-portability: windows-build fixes
merge ns-portability: code changes
merge ns-portability: new docs and barcodes
merge ns-portability: remove tarballs
merge ns-portability: fix line endings and modes