Now you can push your branch to "lyx":
$ git push lyx 2.0.x
How come I have to specify "lyx 2.0.x". Isn't it possible to setup the
branch so that "git push" will do the right thing?
"git push" will by default push to the remote which is tracked by the
current branch. If the current branch does not track anything it will
push to "origin".
To see and edit what is being tracked by a branch, you can type
$ git config -e
There will be something like:
[branch "2.0.x"]
remote = origin
merge = refs/heads/2.0.x
So, the branch 2.0.x tracks the branch "2.0.x" from the remote "origin".
So, you can configure it however you want it.
The hint in the error message says that you have to merge the remote
changes before you push. This is the same as that svn would tell you
that your repo is not up to date.
Most probably the following will solve this:
$ git pull --rebase
In which repository?
In the one from where you are trying to push to the git.lyx.org from.
Vincent