Better Google Chat par JDTX

This plugin provides a number of UI/UX improvements to Google Chat and also adds keyboard shortcuts.

Features:
- Alternate dark mode theme
- Left-aligned chat content (instead of center-aligned)
- Full-width messages that utilize your entire screen space
- A more compact "New Chat" button
- Better spacing between the icons and names of the channel
- Remove the visually noisy text-icons on channels, replace with a simple "#" sign
- Changes the "Unread" squiggle line to be red to be more obvious

Keyboard shortcuts:
- Require Cmd+Enter/Shift+Enter to send a message
- Cmd or Ctrl+Shift+Backspace to mark all unread messages as read