New, cleaner package repository structure.

Package repositories now look like this:

    top-level-dir/
        repo.yaml
        packages/
            libelf/
                package.py
            mpich/
                package.py
            ...

This leaves room at the top level for additional metadata, source,
per-repo configs, indexes, etc., and it makes it easy to see that
something is a spack repo (just look for repo.yaml and packages).

1 files changed, 2 insertions, 0 deletions

diff --git a/var/spack/repos/builtin/repo.yaml b/var/spack/repos/builtin/repo.yaml
new file mode 100644
index 0000000000..54b282db6b
--- /dev/null
+++ b/var/spack/repos/builtin/repo.yaml
@@ -0,0 +1,2 @@
+repo:
+  namespace: builtin