archtrack: Move packages from /packages/stage1 to /packages.
archtrack: Remove 'Maintainer' comments.
archtrack: Remove extraneous blank lines at tops of files.
prep-packages: Add the abilities to remove Id comments and leading blank lines.
prep-packages: Continue on read failure.
list: Add subshells to loops that source PKGBUILD files.
build: Build in the package directories. Make gpg-agent quit correctly.

The build directory was getting cluttered with build remnants. Now we
build where the PKGBUILD files are and move the packages to the build
directory afterwards.

gpg-agent was left running after the script quit. We now run the script
with gpg-agent from within the script itself. This makes gpg-agent exit
when the script does. It feels wrong but I couldn't find a better way.
build: Log errors. Fix the gpg-agent mess.

If a build fails, a message is printed to stderr:

    "'$pkgbuild' failed with error code $?"

gpg-agent is now killed on exit.
build: Fix gpg-agent start error.

gpg-agent's output wasn't being evaluated.
build: Use a dedicated directory for building packages.

There are now three directories involved.
 - packages has PKGBUILD files
 - build is where packages are built
 - repo is where the finished repo lives