Improve dashboard/API/Github discoverability - add page with software comparisson

[bwbroersma]

@stitch made a nice table proposal for the front page of single test, to include a table with features and links to dashboard / API etc., and when to use what. We all agree there should be a page with the information, with links on the front page, about and maybe result page / navigation menu (currently only on the copyright and disclosure page there is a GitHub link).

There should be some explanation it's all open source, the Batch API is an 'instance' of the single test code and that the dashboard uses the Batch API.

My proposal:

Software	Single test	Batch API	Dashboard
Website test	✅	✅	✅
Email test	✅	✅	✅
Connection test	✅	❌	❌
Test size	1	up to 5000*	up to 5000*
Start test	manual action**	API call	manual or periodically scheduled
Result	Webpage	JSON (openapi)	📊 Web report, spreadsheet, 📨 mail (see tour) and Batch API JSON
Languages***	NL, EN	EN	NL, EN
Hosted version	Free & open**	Free, Restricted to limited organisations****	Free, Restricted to limited organisations****
Minimal self hosting resources	2CPUs, 4GB RAM, X GB disk	2CPUs, 4GB RAM, X GB disk	? + a Batch API instance

* default limitations can be changed if self hosted
** scraping is not allowed on the internet.nl Single test instance, please apply for an API account, or host your own API instance
*** More languages can be added in a custom fork
**** see https://dashboard.internet.nl/#/signup and terms of use

Duplicated content (e.g. open source / License) shouldn't be in the table, I think.