Proper custom pkg index support, some tests

- The rebar package index files have been moved off the default path and
  will require a new `rebar3 update`
- Caching of downloaded packages automatically takes place in a path
  relative to the CDN used
- The cache path is not shared with hex as we now write and modify data
  in there arbitrarily
- Basic tests plus the working set for more of them is included

1 files changed, 0 insertions, 0 deletions

diff --git a/test/rebar_pkg_SUITE_data/goodpkg-1.0.0.tar b/test/rebar_pkg_SUITE_data/goodpkg-1.0.0.tar
new file mode 100644
index 0000000..e5b963f
--- /dev/null
+++ b/test/rebar_pkg_SUITE_data/goodpkg-1.0.0.tar