Adding example for future rest UDA @headerParam
Generalize findFirstUDA to findNextUDA
Adding funcattr and typetuple to vibe.internal.meta.all
Adding vibe.internal.meta.UDATuple to work with multiple usage of the same UDA
Add attributes for parameter origin
Server side handling of @headerParam
Handle @headerParam client-side

- Add a string[string] headers__ local variable to the generated function;
- If there's one and only one WebParamAttribute with the name of the parameter we're currently processing (as parameter gets processed in order), we add it to the AA, the key being the 'field' in WebParamAttribute;
- headers__ gets later passed to request() which will add all it's field to the headers;
Fix indentation in vibe.internal.meta.uda
Local import for vibe.internal.meta.uda
Style fix
Small indentation fix for vibe.web.rest
Small optimization: Use InetHeaderMap instead of string[string] in the rest generator
Merge pull request #908 from Geod24/rest-enh-unsplit-2

REST enhancement #1: Allow one to get parameters from headers
Avoid unecessary HTTPMethod -> string -> HTTPMethod conversion