Release v0.0.3

[SabineHaas]

• first of all, fix Fix TES tests #314
• merge Update setup.py #323
• merge Change docstring of demand.py #309
• adapt/check date in changelog.md
• use existing release branch, merge dev into release branch before going on with release protocol
• ❌ check whether Fix GitHub actions for release branches #305 solves [Bug] master tests not triggered for PR into master  #297, otherwise solve.
• make sure Hotfix for failing tests in master build #298 really solves [Bug] master build fails #296
• make sure that all wanted changes are included
• check zenodo doi, add badge to readme Zenodo entry for pvcompare #282
• add contributors to zenodo (for citation)

[SabineHaas]

@Piranias @MaGering
which changes would you like to include into release v0.0.3? --> please refer to issues

• I would prefer to do the release as soon as possible, to fix master build and to get a DOI in Zenodo.
• This could already be the release for @MaGering 's thesis.. ? If you prefer improved code documentation + RTD, we should have one in between, before code changes.
• The tag of this release (befor code changes) will also be the reference for our working paper (version that was used for simulations), right @Piranias ?
• We should do another release end of May for the final meeting, that will still improve the documentation, include fixed issues and update to newest MVS version if possible (also changes in code).

please let me know whether you agree.

[SabineHaas]

@MaGering I have edited the zenodo upload now: contributors, title, description, license..