Releasing xleaflet

Releasing a new version

From the master branch of xleaflet

Make sure that you are in sync with the master branch of the upstream remote.
In file xleaflet_config.hpp, set the macros for XLEAFLET_VERSION_MAJOR, XLEAFLET_VERSION_MINOR and XLEAFLET_VERSION_PATCH to the desired values.
Update the readme file w.r.t. dependencies on xleaflet
Stage the changes (git add), commit the changes (git commit) and add a tag of the form Major.minor.patch. It is important to not add any other content to the tag name.
Push the new commit and tag to the main repository. (git push, and git push --tags)
Release the new version on conda
Update the stable branch to point to the new tag