Changing to secure protocol.

When trying to deploy rdb, it was hanging on cloning the alternator repository.

Cloning manually returned an error.

```

reload@roedovre:~$ git clone 'http://github.com/dingproject/alternator.git' '/tmp/test'
Initialized empty Git repository in /tmp/test/.git/
error: RPC failed; result=22, HTTP code = 400
```
It worked with https
```
reload@roedovre:~$ git clone 'https://github.com/dingproject/alternator.git' '/tmp/test'
Initialized empty Git repository in /tmp/test/.git/
remote: Counting objects: 574, done.
```

It seems that something was changed on github, though I can't find any documentation.