Initial migration to typescript (#845)

This migrates some utilities classes from javascript to typescript.
Nothing special about the migration, mainly added types and made sure
the code adheres to the strict mode.

I have picked some small files so git doesn't think they are the same
since they are "very different".
I hope that in later PRs, when migrating lager files this won't be an
issues.

src/libs/sort-numerically.ts

@@ -0,0 +1,14 @@
+export default function(num1: string | number, num2: string| number) {
+  const a = +num1;
+  const b = +num2;
+
+  if(a < b) {
+    return -1
+  }
+  else if(a > b) {
+    return 1
+  }
+  else {
+    return 0;
+  }
+}