Querystrings proposal for discussion

Created by: robballantyne

Hello,

This is an initial proposal for enabling query string support for all URL's as well as introducing support for json, xml, txt and rss extensions.

This is tested and appears to be working well with Nginx. I do not use Apache so am unsure on how to proceed with modifying the rewrite rules here. Perhaps someone can advise? hopefully it's as simple as Nginx!

Security considerations

Per the design of the plugin (and the original Laravel package) all routes which return a 200 code will be cached. This behaviour is unchanged. An attacker could potentially spam URL's with unused params thereby writing many files to disk.

I would suggest that the end-user of the plugin should be throttling requests with a WAF and returning a 404 if the params sent are invalid, but this is often not the case. Mitigating this attack is probably out of scope for this plugin. The concern should be highlighted, however. Perhaps even make caching for query strings optional via settings.