(core) Refactor more value parsing code into common

Summary:
Following discussion in https://phab.getgrist.com/D3164:

- Change createParser to accept docData and one or two metadata row IDs and let it extract the metadata, so it's more easily usable in the server.
- Change ViewFieldRec.valueParser observable to a function createValueParser.

Test Plan: Existing tests.

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D3172

app/client/lib/ReferenceUtils.ts

@@ -17,9 +17,6 @@ export class ReferenceUtils {
   public readonly isRefList: boolean;
 
   constructor(public readonly field: ViewFieldRec, docData: DocData) {
-    // Note that this constructor is called inside ViewFieldRec.valueParser, a ko.pureComputed,
-    // and there are several observables here which get used and become dependencies.
-
     const colType = field.column().type();
     const refTableId = getReferencedTableId(colType);
     if (!refTableId) {