Allocate (all-or-nothing) machine in Open Stack
===============================================
When allocating machine in Open Stack (OS) from command-line, there are usually
several OS API end-points to talk to (nova, cinder, neutron, ...), and pretty
non-trivial process to follow to get all the pieces together (assign floating
point IP, persistent storage, execute spin-up custom script).  Several commands
are pretty hard to maintain, and that's not what most of the real-world
scripting want --- single command which either does completely everything (or
fails and thus it does "nothing" -> garbage collects all the leftovers).  That's
where `resalloc-openstack-new` scripts helps.  The counterpart is
`resalloc-openstack-delete`.
Basic usage
-----------
Even though this project is tightly related to [1] resalloc project, it might be
useful to anybody:
    1. export all the $OS_* variables into your environment (OS_TENANT_ID,
       OS_PROJECT_NAME, OS_USERNAME, ...), for more info see the "Access &
       Security -> API Access -> Download Openstack RC File" button
       in your OS dashboard or docs [2].
    2. $ resalloc-openstack-new                                     \
            --image            7e9febc7-24f3-41ee-8fbc-5c85b0e35f3c \
            --floating-ip-from c29a0c92-6721-4e83-b9b4-d1a2c7d11495 \
            --flavor           3                                    \
            --name             SERVER_NAME                          \
            --key-pair-id      your-keypair-name-or-id              \
            --alloc-volume     16                                   \
            --post-command     execute-this-command-once-booted.sh  \
            --print-ip
       status: BUILD
       status: BUILD
       ...
       booted server ad7a1782-c475-4173-bb7b-8bb85488e44a
       10.8.248.215
       The only stdout output is the server IP address.
    3. $ resalloc-openstack-delete \
                --delete-everything \
                ad7a1782-c475-4173-bb7b-8bb85488e44a
       running cleanup
       cleaning 01_ip_10.8.248.215
       cleaning 10_server
       deleting server ad7a1782-c475-4173-bb7b-8bb85488e44a
    4. See $ resalloc-openstack-new --help
References
----------
[1] https://github.com/praiskup/resalloc
[2] https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux_OpenStack_Platform/5/html/End_User_Guide/cli_openrc.html