Rule-restricted wildcard match of single subdomain #488

[tom-haines]

Add support for rule-restricted wildcard match of lowest-level subdomain via LRU cache.

This PR:

• builds on PR 1220, applying to any client created via API for example - rather than static clients only, see discussion at issue 448
• far tigher security as per comments by fbsb on PR Make static clients' RedirectURIs to be regular expressions #1220
• in-memory LRU cache of max 500 redirect URI values -> empty string (no valid wildcard) or to regex string to match if all conditions met

[tom-haines]

@postmaxin
I've added globber support and zero, one or more wildcards (wildcards operate within single subdomain portion only).
I also took opportunity to clean up performance and testing aspects, and to use the matcher only on the hostname component to avoid injection type issues as we can enforce end of host stream matches e.g. "example.com" which could otherwise be added to the path component of the URL.
Docs updated.
It's designed in a way that should support utf-8 primary domains as well for cyrillic chars etc.
Ready for next review.

[tom-haines]

This was discussed in open issue #1300 – it was a quick/logical quick so included here, but not relevant to main issue of wildcard support.

[carpenike]

Would also like to see this as well.

[jvanzyl]

This would be awesome to get into the next release! I know everyone is busy but it would be great if this can be reviewed!

[Smana]

Looking forward testing this, could we help making this feature its way to the next release.