For reals fix the canvas conversion logic.

Enhances the HTML rendering logic to support a more standard rgb encoding for streamdeck display purposes.

Adds Tree Style Tabs integration so that tab bookmarks set on the physical device hardware have their color reflected into the Tree Style Tab corresponding to the bookmark.

Focus slot parent descriptor changed to expose the raw bounds rather than attempting to pre-transform to map from CSS pixels to device pixels. Unfortunately, the way Firefox does multi-monitor offset calculations for CSS pixels requires having information about the monitors in use, something that is not exposed to the WebExtension.

Fix bugs where the reported focusSlotId was not properly mapped to the persistent version.

Ugh. Version 0.4.1 was a bug-fix and I hit the "Cancel and Disable Version" button accidentally instead of the "Submit Version" button because I'm used to hitting the right-most button and it's nice and big and red.

Adds the ability to "bookmark" buttons/links in specific tabs and report them to the controller server so that they can be assigned to buttons on the hardware controller. These bookmarks use a session-persisted per-tab permission model so that a rogue controller can only abuse the permissions which have explicitly been granted.

- Allocate persistent tab and window id's through use of the sessions API so that taskolio bookmarks are able to persist across browser restarts. This now requires the "sessions" permission.
- Send focus slots inventory at connection.

This update:
1. Provides the ability to render HTML to images so that the node.js server can use the LCD displays on the NI Maschine Mk3 as part of its interface.
2. Provides more information about tabs open in the browser to the node.js server so that the display can list the pinned tabs of the primary browser window. This includes the title of all open tabs.

Compensate for device-pixel ratio when reporting window coordinates so the window manager can match with its own actual raw screen coordinates rather than logical CSS pixels.