insecure column/attr name is misleading and wrong

[Tom Cammann]

When talking about TLS the 'insecure' option should be used for disabling certificate validation not for disabling TLS. The column so be renamed to avoid confusion as this is a common convention.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/229035

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/229035
Committed: https://git.openstack.org/cgit/openstack/magnum/commit/?id=bc6b7b79bac5abc1b5607369de7f70de095e890f
Submitter: Jenkins
Branch: master

commit bc6b7b79bac5abc1b5607369de7f70de095e890f
Author: Tom Cammann <email address hidden>
Date: Tue Sep 29 17:30:44 2015 +0100

    Rename "insecure" to "tls_disabled"

    When talking about TLS "insecure" is used for describing a situation
    where certificate validation is disabled. However in Magnum it has been
    used to describe disabling TLS entirely. This change modifies this
    column and attribute name to avoid any confusion.

    Co-Authored by: Adrian Otto <email address hidden>
    Co-Authored by: Vilobh Meshram <email address hidden>

    Closes-Bug: #1500953
    Change-Id: Idb3316900fe2b7fb3acd38f57226902ca10e091a