Make the Pre-Election and additional reporting date charts sortable

[djgarr]

Summary

Updating the Pre-Election and additional reporting date charts for more sortability.

On the current (or as of 2020 pre-election and 2021 special election) charts, the only way to filter the chart is to choose a state from a drop down menu. The goal was to see if there was a way to sort the table chronologically as well (Public Records produces a PDF demonstrating the alphabetical and chronological reporting dates (https://www.fec.gov/resources/cms-content/documents/2020pdates.pdf)). This applies to the Congressional pre-election report table, as well as the coordinated communication, electioneering communication, federal election activity, and independent expenditure reporting tables.

Completion criteria

• Create sortability on both election date and state for election tables
• Test extra carefully - it's very important not to scramble the data

[johnnyporkchops]

While it's possible to add sort to a basic table with JS, the existence of the hidden footnote rows adds a layer of complexity making this very complicated, if not impossible. Given the complications involved, I think it's worth evaluating the priority for implementing this before trying to move forward.

[johnnyporkchops]

Created two partially working prototypes for the the Congressional Pre-Reporting table but these are still not complete and only apply to that one table on a FullWidth page. The issue author, @djgarr has said that this feature is currently a nice-to-have and not a must-have so we agreed to shelve this work for now.
The possible approaches, for future reference, are to

1. Export reporting-dates-tables.js as a module (instead of a "page)" and include jQuery datatables node-module via a require variable. Then apply datatables to the table in the script and enable its sorting functionality. (this one also requires making the footnotes to be added on-click instead of the current way of adding when the table loads(with hide/show on-click), so that there are no colspans that confuse Jq Datatables sorting functionality on-load)

   var $ = require('jquery');
   require('datatables.net');
   require('datatables.net-responsive');
   var moment = require('moment');
   
    ...
   
    $(this.dates_table).DataTable( { ....
   
    ```
   
   

2. Use a native JS table sort function. Will likely also require making the footnotes to be added on-click instead of when the table loads so that there are no colspans that might confuse sorting functionality on-load)

@johnnyporkchops Has a version of the JS which uses new logic to add footnotes on-click, instead of the current on-load(with hide/show)