PSD Layer Viewer is an extension for the code editor Brackets that allows to view PSD files, export layers, generate CSS code.
It is a very simple extension that shows panel with site http://psd.keyangxiang.com/ which is an awesome tool to work with PSD files.
The extension have one little issue: "Export PNG" button doesn't work, so you should use drag and drop for saving image above the button.
PSD Layer Viewer is installed from the Brackets Extension Manager.
Ctrl-Shift-P (Windows), Cmd-Shift-P (Mac)
Author of Online PSD Viewer: Keyang Xiang