Validate Link

The idea of this plugin is coming from my work.
I’ve been assigned a lot tasks for cleaning broken links.
Which is so bored.
Editors are lack of basic HTML skills, they always tried to insert links like such:

• href=”www.abc.com
• href=”awesome-slug

Apprently, they will finally result in

• http://mydomain.com/current-page/www.abc.com
• http://mydomain.com/current-page/awesome-slug

So this plugin is to display a warning message in WordPress dashboard,
in case there is such invalid URLs in post content.