* include promise polyfill
* remove es6
* add viewBox to every icon
* change self closing to explicitly closing tags
* replace window.scroll.. with document.documentElement.scroll..
* verify document.activeElement.blur() is a function before calling
* fix visuals of color chooser (colorpicker still sometimes buggy)
* do not attach to mouseleave event in IE
* attempt removal with usecapture true in IE as well, this fixes the tool switching issue
* fix text tool for IE
* fix cursor for IE
* change curMode to boolean and rename to 'active'
* replace minified canvascolor with unminified code
* replace if else structure with switch statement
* compile polyfill for each browser individually
* remove static polyfills from board.js
* Fix broken js reference
* Fix unused variable and empty console log
* Allow serving non-minified polyfills for easier debugging
* Add proper caching for polyfill.js
This request is on the critical path, we should try to make it fast
* Include more polyfills
All the DOM polyfills were missing
* Update dependencies
* Add missing polyfill
Our custom polyfill was deleted, but the one from polyfill-library hadn't been added
* Remove feature detection for Node.contains
We now have the function in the polyfills
* Update polyfill caching logic
* Remove content-Length header
Co-authored-by: @lovasoa
