### Please describe the problem.
Cannot add gitlab repository on Android.

### What steps will reproduce the problem?
After attempting to add a gitlab repository on git-annex assistant, I am presented with a ssh key and prompted to add it to my gitlab account. After doing so and continuing, git-annex assistant returns to the same page and presents the ssh key again. Attempting to continue repeats the cycle as the ssh key is presented over and over.

### What version of git-annex are you using? On what operating system?
Stable version for Lollipop (I experienced this same error on Kit Kat ~6 months ago but could not resolve it at that point)
Android 5.0 git-annex.apk

### Please provide any additional information below.
In the git-annex assistant log I see:

    No ECDSA host key is known for gitlab.com and you have requested strict checking. 
    Host key verification failed. 
    No ECDSA host key is known for gitlab.com and you have requested strict checking. 
    Host key verification failed. 
    fatal: Could not read from remote repository
    
    Please make sure you have the correct access rights and the repository exists.
    Host key verification failed.
    Host key verification failed.
    fatal: Could not read from remote repository.

I resolved the issue by opening a new terminal window, attempting to connect to gitlab (ssh git@gitlab.com), verifying the ECDSA key against the gitlab website (https://about.gitlab.com/gitlab-com/) and accepting the key. The file .ssh/known_hosts was created. The gitlab repository could then be added in git annex assistant.

The lack of information about the error presented to the user in git annex assistant was part of the problem.


[[!format sh """
# If you can, paste a complete transcript of the problem occurring here.
# If the problem is with the git-annex assistant, paste in .git/annex/daemon.log


# End of transcript or log.
"""]]

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)