Support '\' as a linebreak

[seaspeak]

Markdown uses two trailing spaces as a linebreak. Some think it's a malpractice and ugly, so some parsers also support '\' as a linebreak. I can't find it in offical spec, but I think it is plausible and preferable.

[simov]

I didn't know about that.

Either way that's a compiler/parser issue. Officially Markdown Viewer is bundled with marked and remark so the issue should be addressed there. I can only bump the version here if there is a fix.

Alternatively you can clone the compilers branch and try with the rest of the supported parsers.