Ruby COMPATIBILITY CONCERNS - Relevant to 1.4.0 release

In r20677, I deleted a typemap that had been added to the Ruby bindings
since 1.3.x, which caused an undeniable compatibility break, by changing
the return type of svn_repos_get_committed_info().

However, having done so, the Ruby tests now fail, and preliminary
investigation suggests that there may be more insidious
incompatibilities in the Ruby bindings between 1.3.x and 1.4.x.

This isn't anyone's deliberate fault, but collectively as a team, I
think we've failed to explicitly define a compatibility policy for the
Ruby bindings. This has led to the current situation in which some
portion of the committers expect the bindings to follow the same
compatibility rules as the rest of the project, whilst those committers
most closely focused on the Ruby bindings seem to have been assuming
it's OK to incompatibly change interfaces in a minor release.

So, in conclusion, ouch!

How do we want to proceed from here?

Max.