Make {{Firefox_for_developers}} macro smarter

[SebastianZ]

The {{Firefox_for_developers}} macro currently simply lists all versions of Firefox up to a maximal version given as constant in that macro.

To avoid having to maintain that constant manually, the macro should base the display of the version links on the Firefox release dates.

The release dates are currently maintained in the {{CompatGeckoDesktop}} macro.

The idea is to extract the release data from that macro into a new {{firefoxReleaseDates}} macro (or store the data somewhere outside of the mozilla/kumascript, or even read it directly from the release calendar) and change the {{Firefox_for_developers}} macro to read the data from that source.
Based on that data, the macro would display the release links up to the newest Firefox Nightly. The currently displayed release page may be displayed differently, e.g. as plain text instead of a link or somehow highlighted.

Sebastian

[SebastianZ]

Example for the things above:
Current shown page is for Firefox 51 and the latest Nightly is 54 (based on the release dates data source), then the macro should list links to all versions from 54 down to version 25 (i.e. 30 versions) and don't link or highlight 51.

Sebastian