Add templates for source with just version numbers

[Micket]

Adding templates for the common %(version)s.tar.gz and v%(version)s.tar.gz sources.

E.g.

1. VERSION_TAR_GZ
2. VVERSION_ZIP

I didn't know a better option but to append an extra V for the second option.

I haven't tested anything yet, throwing it out there to gauge the response first.

[Micket]

ping @Flamefire who i think has explicitly requested this before.

[Flamefire]

Thanks for that

One alternative to VVERSION_<ext> could be V_VERSION_<ext> which makes it easier to see the "v" while being a single char longer

And maybe we should keep the SOURCE_ suffix at least for discoverability among the other templates