Change LyX release numbering to Semantic Versioning

[José Abílio Matos]

On Wednesday, January 13, 2021 9:48:58 AM WET Jean-Marc Lasgouttes wrote:
> I do not really like this. I find it very useful to add weird character
> in a version string to indicate that the version is not a regular one.
> 
> JMarc

This is what I call the "Paris Syndrome", a mild form of the "Stockholm 
Syndrome". :-D

On a more serious note, I do not insist on the particular use of the x.0 
convention. I find it elegant and it gives a nice justification, for example, 
why gcc stable releases always starts at .1. FWIW gcc started the new 
numbering scheme at version 5, and it already the seventh release where this 
numbering schme is used.

In Fedora Rawhide (to be Fedora 34) the current version of gcc is 11.0.0. That 
immediately shows that this is not the stable version. The first stable 
version will be 11.1.
-- 
José Abílio