Support base_url for internal links

[arjunsuresh]

This PR will enable any github fork to run the docs website from their fork by just adding q2a.github.io or the fork repo name as the base_url.

[arjunsuresh]

URL of a working fork site: https://gateoverflow.github.io/q2a-docs/

[svivian]

Thank you for the contribution, however, I don't understand the use case. The docs aren't intended to be hosted on other websites. To make changes you can use Jekyll and run it locally as described here. Let me know if I am missing something.

[arjunsuresh]

Thank you for checking @svivian . Actually the use case is to make it easier for others to give PRs to the official documentation. For example, with this change, I can do edits on github, verify all the changes are as expected and then give a PR - all on a browser without worrying about any setups. Running jekyll locally is not very difficult - but it is still harder than just editing on a browser.

[svivian]

How does that work? For example I have a fork of the docs repo here: https://github.com/svivian/q2a.github.io - is there a URL I can use to view my copy of the docs online?

[arjunsuresh]

yes. But one problem is there - the fork name - the default "q2a.github.io" won't work as it is reserved by github.io. If you rename the fork to "q2a-docs", then the url will be https://svivian.github.io/q2a-docs (In the fork settings, github pages must be enabled)