(core) move home server into core

Summary: This moves enough server material into core to run a home server.  The data engine is not yet incorporated (though in manual testing it works when ported).

Test Plan: existing tests pass

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D2552

app/common/tbind.ts

@@ -0,0 +1,15 @@
+/**
+ * A version of Function.bind() that preserves types.
+ */
+
+// tslint:disable:max-line-length
+
+// Bind just the context for a function of up to 4 args.
+export function tbind<T, R, Args extends any[]>(func: (this: T, ...a: Args) => R, context: T): (...a: Args) => R;
+
+// Bind context and first arg for a function of up to 5 args.
+export function tbind<T, R, X, Args extends any[]>(func: (this: T, x: X, ...a: Args) => R, context: T, x: X): (...a: Args) => R;
+
+export function tbind(func: any, context: any, ...boundArgs: any[]): any {
+  return func.bind(context, ...boundArgs);
+}