(core) Adding colors to toast notification

Summary:
Styling toast notification. Adding colors and icons.
In Grist, changed the default style for errors (will be shown in red), and a style for
Linked copied to clipboard (will be shown in Green).
All other colors are not used currently, left for another diff.

Test Plan: manual

Reviewers: georgegevoian

Reviewed By: georgegevoian

Differential Revision: https://phab.getgrist.com/D3053

static/ui-icons/UI/Info.svg

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   id="svg8"
+   version="1.1"
+   viewBox="0 0 16 16"
+   height="16px"
+   width="16px">
+  <defs
+     id="defs821" />
+  <title
+     id="title895">Icons / UI / InfoSolid</title>
+  <path
+     style="clip-rule:evenodd;fill-rule:evenodd"
+     id="path816"
+     d="M 16,8 A 8,8 0 1 1 0,8 8,8 0 0 1 16,8 Z M 9,4 A 1,1 0 1 1 7,4 1,1 0 0 1 9,4 Z M 7,7 a 1,1 0 0 0 0,2 v 3 a 1,1 0 0 0 1,1 H 9 A 1,1 0 1 0 9,11 V 8 A 1,1 0 0 0 8,7 Z" />
+</svg>