In case Kolla's users want to deploy with both of
binary and source image, we should have a variable
install type that define install type for each project.

We also add specific image tag for each Openstack project.

This commit is implemented for Ironic, Kabor,
Keystone project and iscsi as well.

Change-Id: I134d840b1c0e24171a32dec0c7daa6dc2e9ecd87
Implements: blueprint mixing-binary-and-source-image