We need to add some changes to the version checker, that is executed @ integration.moodle.org in order to better control versions in every branch.

Basically the point to add is to be able to specify, per branch (aka, per job), which is the interval versions (8 digits, YYMMDD) that we accept as valid for a given branch.

So, for example, we can say that all the 39_STABLE versions must be between 20180514 (when the megabump happened and all the plugins have it) and 20180517 (the release one). So, any version out from those limits will raise an error.

Or we can just specify the initial number, meaning that any number equal or higher is ok. Or the opposite, specify the final number, so any number lower or equal is ok.

This specially needed under multiple development branches because we must ensure that there isn't any overlapping of versions between branches ever. So, for example:

• 3.10 allowed versions will be between the day we create the branch and 3.10 release date.
• 3.11 allowed versions will be between the day we create the branch and 3.11 release date.
• 4.0 allowed version will be any date after 3.11 release date.

As you can see, disjoint intervals, no overlapping. That's the point. The intervals will be configurable via env var.