jf_activity: paginated list in ui

added POST route for pagination to activity route, a count route, and
modified Search and PaginatedList a bit to support lists without search
fields (essentially just running an empty search). Visible by clicking
on a user's name in the accounts tab.

ts/modules/settings.ts

@@ -14,7 +14,6 @@ import {
 } from "../modules/common.js";
 import { Marked } from "@ts-stack/markdown";
 import { stripMarkdown } from "../modules/stripmd.js";
-import { PDT } from "src/data/timezoneNames";
 
 declare var window: GlobalWindow;