Standalone Fuel 9.x ISO images required.

Detailed bug description:

If someone faces a bug that prevents the install of Fuel 9.0 then a fix released for Fuel 9.1 won't be of much help considering they can't install Fuel 9.0 to begin with.

For example, customer is facing this bug:

https://bugs.launchpad.net/fuel/+bug/1605740

as such, they cannot install Fuel 9.0 or any other updates to address the issue. Custom ISO needs to be built (unless there are other ways I am unware of).

Steps to reproduce:
1. Experience bug that hinders deployment of Fuel 9.0 (https://bugs.launchpad.net/fuel/+bug/1605740
)
2. Fix cannot be applied since Fix requires update to 9.1 and 9.0 cannot be installed.

Expected results:

Fixes that address deployment issues with Fuel 9.0 should merit standalone 9.x images to avoid these issues.

Actual result:

Cannot instal Fuel 9.0 despite there being a fix.

Reproducibility:
In this case, 100%
Workaround:
 Build custom images
Impact:
Depending on the bug in question. In my case, it hinders deployment of Fuel.