Improve routing - regular expressions

[mabar]

• {id \d+}
• {lang [a-z]{2}} - I'm not sure about syntax - regex uses {} characters for range. Should we use escaping or switch to <var>?
• greediness? - some systems uses / in their identifiers - currently cannot be sent into apitte

Question is how matching should exactly act. Route contains {id \d+}, so should string_id cause error like datatype is defined in @RequestParameter or should not match? (First variant is preferred by me)

[mabar]

Seems like slashes in identifiers could be huge problem. Also, we need to be compatible with openapi. See that discussion for more info, people noted there some important things.

Regex for parameters will be implemented as @RequestParameter(name="id", type="string", pattern="^\d{3}-\d{2}-\d{4}$"), to be compatible with openapi