0) Update develop and master, merge develop into master

update the version number in CMakeLists.txt, src/apex/CMakeLists.hpx and doc/Doxyfile.in and docs/webdocs/install.md

git checkout develop
git pull
git checkout master
git pull
git merge develop

1) Generate a changelog from the last tag:

git log $(git describe --tags --abbrev=0)..HEAD --pretty=format:'<li> <a href="http://github.com/UO-OACISS/apex/commit/%H">view commit &bull;</a> %s</li> ' --reverse > changelog.txt

2) create a new tag

git tag -a -F changelog.txt v2.1.1

3) push that tag, merge iwth master

git checkout master
git pull
git merge develop
git checkout develop
git push origin
git push --tags origin

4) Update github, make release
