Allow for the use of an external inventory

It makes sense to allow a user to provide their own inventory as needed.
this change simply allows a user to explort the option "MNAIO_INVENTORY"
prior to running `build.sh` which will allow them to define their own
inventory using the general purpose build script.

Change-Id: Ib5233da1bf34620ec8bf3decc4ecd51823b50b79
Signed-off-by: Kevin Carter <kevin.carter@rackspace.com>

multi-node-aio/README.rst

@@ -95,6 +95,10 @@ to change this password please edit the pre-seed files.
 ``build.sh`` Options
 --------------------
 
+Set an external inventory used for the MNAIO:
+  ``MNAIO_INVENTORY=${MNAIO_INVENTORY:-playbooks/inventory}``
+
+
 Set to instruct the preseed what the default network is expected to be:
   ``DEFAULT_NETWORK="${DEFAULT_NETWORK:-eth0}"``
 

multi-node-aio/build.sh

@@ -20,12 +20,12 @@ source bootstrap.sh
 source ansible-env.rc
 
 ansible mnaio_hosts \
-        -i playbooks/inventory \
+        -i ${MNAIO_INVENTORY:-"playbooks/inventory"} \
         -m pip \
         -a "name=netaddr"
 
 ansible-playbook -vv \
-                 -i playbooks/inventory \
+                 -i ${MNAIO_INVENTORY:-"playbooks/inventory"} \
                  -e setup_host=${SETUP_HOST:-"true"} \
                  -e setup_pxeboot=${SETUP_PXEBOOT:-"true"} \
                  -e setup_dhcpd=${SETUP_DHCPD:-"true"} \