Here is a design that enables backporting capabilities (i.e.
backwards-incompatible API changes) to maintenance branches of FreeIPA.
The premise is that no branched development occurs on the maintenance
branch, only single targeted changes are brought back.
I believe it solves the problem rather nicely, and the implementation
would be pretty straightforward.
The downside is that uses weird API versions like
'2.347+backported_capability' (which are currently valid API versions,
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