rhbz1110627 zanata init

https://bugzilla.redhat.com/show_bug.cgi?id=1110627
and https://bugzilla.redhat.com/show_bug.cgi?id=1038852

Depends on https://github.com/zanata/zanata-api/pull/15 and https://github.com/zanata/zanata-server/pull/520
> This is copied from web UI. We could check for uniqueness since we already get hold of all projects on server (can not guarantee update to date but still). Mentioning unique at least will let them aware they may see error coming from this.

Then we could fix it on the web UI as well - since this is an interactive program, we can avoid overloading users with information up-front. I do not expect anyone to be totally shocked to hear that someone else already used a name, so I think the value of pre-warning them of a possible error is not worth the cost of making the user less comfortable by giving them information that they have no way to act on (the user is not a Java compiler, we don't need to tell them about every checked exception that might happen).