Feature/use second level mui imports (#743)

* Require "Theme" to be passed to "SxProps"

Decreases typescript performance otherwise

* Disallow "top" and "third-level" MUI imports

* Exclude "node_modules" in tsconfig

tsconfig.json

@@ -34,6 +34,7 @@
   "include": [
     "src"
   ],
+  "exclude": ["**/node_modules", "**/.*/"],
   "references": [
     {
       "path": "./tsconfig.node.json"