Add keyboard shortcut to insert from middle-click buffer in Linux

• OS version and name: Ubuntu 16.04
• Hyper version: Hyper 1.0.0
• Link of a Gist with the contents of your .hyper.js: Default contents
• Relevent information from devtools (CMD+SHIFT+I on Mac OS, CTRL+SHIFT+I elsewhere): NA
• The issue is reproducible in vanilla Hyper.app: Is Vanilla

Issue

Coming from gnome-terminal, I expected Shift+Insert to paste from middle-click buffer but instead it does exactly the same as Ctrl+Shift+V and inserts the contents of the clipboard.

I couldn't find another keyboard shortcut to do it either. Is there a way to edit keyboard shortcuts?

At least I can perform this action using the mouse (middle click) for now but that's inconvenient since I like to do most things without leaving the keyboard.

Anyway, I would like it if Shift+Insert would paste from middle-click buffer (also called primary or selection buffer) like it does in gnome-terminal. See for example http://unix.stackexchange.com/questions/178070/why-does-shiftinsert-paste-from-clipboard-in-some-applications-and-primary-in-o#answer-178401

Start by locating Hyper's keyboard shortcut handling and its Linux middle-click or primary-selection behavior. Reproduce the issue on Ubuntu 16.04, then verify that Shift+Insert inserts the middle-click buffer while the existing clipboard paste shortcut continues to work.