Auto-build -gles twins

[Michał Sawicz]

The list of packages that require -gles twins is well known, the train already has checks for those.

With the recent refactor of how the -gles packages find their source and version number, there is only need for MPs against the -gles packaging branch when the packaging changes.

It would be nice if the train, where there isn't a MP for the -gles package, would simply take the upstream /gles branch with no changes (e.g. for lp:qtmir - lp:qtmir/gles). Maybe we need a map, or maybe we just require for all projects to register a /gles series, your call :)