list: cleanup, include offset in DateAttempt

included UTC offset in minutes in DateAttempt, will be used shortly.
Also moved this stuff (ParsedDate, DateAttempt) to the common d.ts, and
the method for parsing from a string (now parseDateString) to common.
Also pre-emptively load the user cache when the admin page loads.

ts/typings/d.ts

@@ -161,5 +161,20 @@ interface PaginatedReqDTO {
     ascending: boolean;
 };
 
+interface DateAttempt {
+    year?: number;
+    month?: number;
+    day?: number;
+    hour?: number;
+    minute?: number;
+    offsetMinutesFromUTC?: number;
+}
+
+interface ParsedDate {
+    attempt: DateAttempt;
+    date: Date;
+    text: string;
+};
+
 declare var config: Object;
 declare var modifiedConfig: Object;