Unable to process REST call correctly

[ncoe]

While trying out the rest example using the firefox RESTClient to send the request, I got a stack trace indicating the the content-type header was not set to "application/json" as it expected. The actual value sent down was "application/json; charset=UTF-8". The method jsonMethodHandler in http/rest.d expected the exact string "application/json". By importing std.algorithm and using the check:

enforce(!req.headers["Content-Type"].findSplit("application/json")[1].empty, "The Content-Type header needs to be set to application/json.");

I was able to get the response i expected. There needs to be some better handling when additional information is present in the header.

[s-ludwig]

One way to improve the handling in general would be to add a full header parser (e.g. issue #12) and not have standard headers in the req.headers map at all, which would also have the nice side effect to reduce the number of required memory allocations. I haven't decided yet which way has the better arguments for it.

For now, there are generally some special properties in HttpRequest/HttpResponse and I've also added contentType/contentTypeParameters, which is used everywhere now instead of manual str.split(';').

[ncoe]

Thanks for the quick response. That commit works great.