MD standard HTML tags are not ignored during conversion

IF you create a documentation page under GitHub (edit mode), there is no garantee that the Doc web site will look good even if the page under Git Hub is correct.

In particular the <br> HTML tag which sould be supported in MD are ignored during conversion.

See delta between

https://github.com/automotive-grade-linux/docs-agl/blob/master/docs/getting-started/troubleshooting.md#configuring-the-audio-hardware

http://docs.automotivelinux.org/docs/getting_started/en/dev/reference/troubleshooting.html#configuring-the-audio-hardware