Remove reliance on github about gitbook

[coalman]

My guess (I'm not a dev and am about to try this out myself): It seems like it would build the files, like a static site generator. You could build the files and then upload them to your own private servers. All you really should need is a web server that can serve static files.

[SamyPesse]

Thanks to @mintbridge (#20), you can use te option --githubHost=<url> to use another host than GitHub (like Bitbucket) for the links "About", "Issues", ... We can probably handle an empty host and don't show up these links.

GitBook generate a static website, you can copy the folder to a static server and it will works fine. GitBook only use the githubId (example: GitbookIO/javascript) and the githubHost (https://github.com) for the links "About", "Issues", ...

[mrpotes]

@speedRS I fixed this in pull request #43 - you no longer need a git host to be specified, but without one you do need to specify a title (using -t or --title).

[speedRS]

Thanks guys. Will give it a try this weekend.