Added option to open Instapaper from context menu

Option shows up under behavior
Added option to open Instapaper by double clicking ChromeToPaper button
Revert "Updated github url"

This reverts commit 3d406334d37866a8d0a19952b040e135fba5972e.
Change README format from plain text to markdown
Stop tracking zip files
Updated to version 2.6.2

Updated welcome page to reflect new changes
Updated version in json
Merge branch 'master' of https://github.com/jamesmkwan/ChromeToPaper

Conflicts:
	README.md