In case the remote repository is not empty (this is the case if you are using IBM DevOps on hub.jazz.net) then you need to use the following sequence:
cd <localDir>
git init
git add -A .
git pull <url> master
git commit -m "message"
git remote add origin <url>
git push
EDIT 30th Jan 17: Please see comments below, make sure you are on the correct repo!