Revert "Remove vendored libjuju"

This reverts commit 9d18c22a0dc9e295adda50601fc5e2f45d2c9b8a.

Change-Id: I7dbf291ccd750c5f836ff80c642be492434ab3ac
Signed-off-by: Adam Israel <adam.israel@canonical.com>
diff --git a/modules/libjuju/docs/api/modules.rst b/modules/libjuju/docs/api/modules.rst
new file mode 100644
index 0000000..9722a6a
--- /dev/null
+++ b/modules/libjuju/docs/api/modules.rst
@@ -0,0 +1,31 @@
+Public APIs
+===========
+
+It is recommended that you start with :doc:`juju.model` or :doc:`juju.controller`.
+If you need helpers to manage the asyncio loop, try :doc:`juju.loop`.
+
+.. toctree::
+
+    juju.action
+    juju.annotation
+    juju.application
+    juju.cloud
+    juju.constraints
+    juju.controller
+    juju.delta
+    juju.errors
+    juju.exceptions
+    juju.juju
+    juju.loop
+    juju.machine
+    juju.model
+    juju.placement
+    juju.relation
+    juju.tag
+    juju.unit
+    juju.utils
+
+.. automodule:: juju
+    :members:
+    :undoc-members:
+    :show-inheritance: