Enhance ]ListVersions: add an -all flag

[aplteam]

Currently, when ]ListVersions is called without an argument is throws a VALUE ERROR without a reasonable error message.

This could be solved by adding a flag -all, resulting in a list with all packages with the very latest version of each major version.

In other words, in such a case, no argument (package name) is required and would be ignored when provided anyway.

[aplteam]

It might be an idea to add -group= and possibly tag= as well, which are only processed in conjunction with the -all flag.

[aplteam]

The bug has been fixed in 0.46.0

That leaves the extension with the -all flag.

Implementing the -group= and -tags= options seems overkill