* Updating client dependancies. Switching to using yarn.
* Updating React
* Moving pure components to using function syntax (performance gains with newer react version)
* Updating client dependancies.
* Ignore .yarninstall
* Enabling pre-lockfile because it's the entire point of using yarn.
* Removing old webpack config
* Moving to new prop-types
* Fixing ESLint Errors
* Updating jest snapshots.
* Cleaning up package.json
Improving help text margins
Updating changes for get link and create post files
Fixing icon for select team screen
Fixing styles for select team button
Adding improvements to posts UI
Adding improvement to post layout
Updating changes for post controls
Updating z-index for sidebar--right
Updating help text position
Fixing code for posts
Fixing css for post view
Pushing improvements for posts view
Updating changes for post view
Updating post layout
Fixing system time css
Updating header for system posts
Updating post css
Removing opacity and changing color for system messages
Simplifying root post and system post behaviour
Removing images from compact view
Updating help text for display
Updating embed preview text for advanced option
PLT-3490 - Fixing RHS issue on Edge
