Fixes issue #839

[tommcd]

Fixes issue #839

[s19110]

The link fixes are fine. I added a suggestion for handling the invalid links in the README_TEMPLATE.md

[tommcd]

Hi @s19110
While starting to edit the template I've noticed other issues: for example the bibliography example which we then explain is to be in Harvard style does not have the reference key in Harvard style, it should be "Python Software Foundation n.d.".
I think it would be clearer to give concrete examples with working links for the Related Guidelines, just copy from one of the existing articles? And finally i think we could add a little more explanation of how to use the template in the form of inline comments, for example:

<!-- 
Write your first sentence as a clear statement of the rule to be followed, such as 'Ensure that...' or 'Do not...'. 
The subsequent sentences in the introduction should provide context, motivation, and reasoning behind the rule.
-->

I think it's best to create a new issue for this.