implement versioning workflow

[tomkralidis]

(cc @alexandreleroux)

@chris-little @iedwards should we introduce version tags as part of WorldWeatherSymbols? This would help in cutting releases of the repository as well as the pre-generated PNGs.

I would suggest the semver approach, but I'm good with whatever approach works for you, and keep consistent.

[alexandreleroux]

I know the question is not addressed to me, but I'm all in favor of version tags. Version tags is the only way anyone can validate which version they're using and why outputs may vary from other users.

[alexandreleroux]

I have a suggestion in harmony with the semver version numbering. What about renaming current versions from 'V05' to version 0.5? 'V04' would be '0.4'. Etc.

Let's leave 1.0 for the initial official version, and subsequent versions would move up the ladder according to semver best practices.

[isedwards]

I say we cut a 0.4.0 right now to stamp a version change, and move onwards
from there per below with subsequent changes. [@tomkralidis]

Tom, +1 From me. [@chris-little]

+1

[tomkralidis]

FYI 0.5.0 released https://github.com/OGCMetOceanDWG/WorldWeatherSymbols/releases/tag/0.5.0.

Will now repurpose things for release workflow, like add a VERSION.txt file, moving parts of README.md to HISTORY.txt, etc.

[tomkralidis]

@alexandreleroux let's generate a WorldWeatherSymbols-0.5.0-png.zip and add it to the download URL and release.

[alexandreleroux]

+1 will do. Please generate the file to your liking, send it my way and I'll add it at the current URL.

[tomkralidis]

FYI GitHub releases support binary uploads, so I've moved the .zip to there. Thanks @alexandreleroux for hosting at slashgeo as interim.