A very simple Open in Browser Atom.io Package. This allows you to right click and have a menu that will open the current file in your default program. That opens that extension. Files will open in your default browser or application.
Update by "MetaMemoryT"
Now able to right click on tree-view and select "Open in browser"
Update by "mesosteros"
Replace editor class with atom-text-editor
tag.
Shortcut was conflicting with meteor developers who use Ctrl-Alt-M in
Meteor.js packages for Atom, so use Ctrl-Alt-Q instead.
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.