Implemented bringing url up in incognito window

Added an (incorrect) icon so the add-on could be tested.
Implemented bringing up the incognito window.
Cleaned up manifest.json to actually work.
Tested loading into chromium.
Tested with a random google search page.
Updated roadmap with item completion.
Merge branch 'master' of github.com:feonixrift/BubbleLens

Perils of having edited the readme in the wrong place.