Recommend return to semantic versioning from date-oriented version numbers.

[dilijev]

This project doesn't really change that much over time, and because we update the version number to the month and year of the release, I think it is difficult for users to know how big the changes are happened. Between some releases we fix a lot of issues and add features (minor updates), but in other releases we mostly maintain the project and keep things stable (patches). So far, I don't think any major UI changes or functionality changes have occurred that would constitute major updates.

Since the program hasn't changed much since it left beta, I would suggest that we are still effectively on version 1.x.x.

However, it would probably be confusing if we went backwards in the numbering scheme, so we can continue to use the date of release, while also using a semantic versioning scheme, by putting the semantic version numbers after the date.

Something like:
wxMaxima 14.10 (1.4.2)

See semantic versioning guidelines: http://semver.org/

Considering that we don't have a public API in the sense that we are not a library or a package or service to be used by other applications, we can base the updates on how large the changes are.