Release v0.3.1 - Githubissues

Draft a Zenodo archive (to be done by a manager on Zenodo)

[x] Go to the Zenodo entry for this project (find the link to the latest Zenodo release on the README.md file)
[x] Create a "New version" of it.
[x] Delete all existing files
[x] Copy the reserved DOI to this issue
[x] Update release date
[x] Update version number (following Semantic Versioning) with a leading v (v1.5.7)
[x] Add as authors any new contributors who have added themselves to AUTHORS.md
[x] Review author order to make sure it follows the guidelines on our Authorship Guide
[x] Save the release draft

[x] Generate a list of commits between the last release tag and now: git log HEAD...v1.2.3 > changes.rst
[x] Edit the list to remove any trivial changes (updates by the bot, CI updates, etc).
[x] Organize the list into categories (breaking changes, deprecations, bug fixes, new features, maintenance, documentation).
[x] Add a list of people who contributed to the release: git shortlog HEAD...v1.2.3 -sne
[x] Add the release date and Zenodo DOI badge to the top
[x] Replace the PR numbers with links: sed --in-place "s,#\([0-9]\+\),\`#\1 <https://github.com/fatiando/PROJECT/pull/\1>\`__,g" changes.rst
[x] Copy the changes to doc/changes.rst
[x] Make a Markdown copy of the changelog: pandoc -s changes.rst -o changes.md --wrap=none
[x] Add a link to the new release version documentation in README.rst
[x] Open a PR to update the changelog
[x] Merge the PR

After the changelog PR is merged:

[x] Draft a new release on GitHub
[x] The tag and release name should be a version number (following Semantic Versioning) with a leading v (v1.5.7)
[x] Fill the release description with a Markdown version of the latest changelog entry (including the DOI badge)
[x] Publish the release

A PR should be opened automatically on the project feedstock repository.

[x] Add/remove/update any dependencies that have changed in meta.yaml
[x] If dropping/adding support for Python/numpy versions, make sure the correct version restrictions are applied in meta.yaml
[x] Merge the PR