Add redimentary group support

src/components/Avatar.scss

src/components/Avatar.tsx

src/components/GroupPreview.scss

src/components/GroupPreview.tsx

src/components/LinkPreview.tsx

src/matrix-cypher/matrix-cypher.ts

src/matrix-cypher/schemas/GroupSchema.ts

src/matrix-cypher/schemas/index.ts

src/utils/cypher-wrapper.ts