Here is small HOWTO release new version of Stratagus (and also Wargus/War1gus/Stargus/...)

Increase version in file:
 CMakeLists.txt

You can do
 gbp dch
to generate a debian changelog update.

Update changelog in file:
 doc/changelog.html

Increase version and update changelog for debian:
 dch -vNEWVERSION
 dch -r

Update copyright information for Debian:
 debian/copyright

It's a good idea to ensure the debian build works before taggging:
 gbp buildpackage

Create the doxygen documentation by building with -DENABLE_DOC=ON
Create the lua function bindings overview by running the Python script doc/lua/generate_index.py
Copy the generated doxygen and the generated lua bindings html to the website storage.

Tag the new release in https://github.com/Wargus/win32-stratagus-dependencies
and wait for it to run through on the Appveyor CI. This will automatically
cause a release with the tag name to be created, and the windows dependencies
will be uploaded there.

Tag the new release here and wait for it to run through the CIs. Appveyor and
Travis will upload new versions for Windows and OSX.
 git commit -a -m "Release version <version>"
 git tag <version>
 git push --tags origin master

Go to Launchpad to trigger building new debian packages.

For Wargus/War1gus/Stargus we have a release.rb script. Run it without any
arguments, and it will tell you how to call it to start the release process
for this particular project.

Finally, update the download links for the stable versions in the
wargus.github.io repository.