Should support opening relative links to markdown

[dwlf]

On January 30, 2013 relative links in markup files was added to github, https://github.com/blog/1395-relative-links-in-markup-files

Clicking on [a relative link](other_file.md) does not work.

Env
markdown-preview 0.71.0 in Atom 0.96.0 on Mac OS X 10.9.2.

Actual Result
No action.

Expected Result
A new preview tab with the linked md file.

Additional Details
Github Pages now supports relative links, as documented December 5, 2016 https://github.com/blog/2290-relative-links-for-github-pages

[IjzerenHein]

Yes, support for working links would be awesome. Especially when testing your markdown-file, so see whether internal and external document links work correctly. +1

[FunTimeCoding]

+1

[davidhesselbom]

+1

[Jcamilorada]

+1

[phairow]

+1

[dlip]

+1

[bojidar-bg]

+1!

[pkeir]

+1

[medfreeman]

+1

[forthright48]

+1

[tkent]

+1