lib-http: Added a function to obtain a message suitable for logging from a response object. This prevents logging internal error codes (>= 9000).

lib-http: Explicitly define the start of the range of internal response status codes.

lib-http: remove http_header_field from http_response

global: unsigned int:1 -> bool:1 perl -i -pe 's/unsigned int ([^,:;]+):1;/bool $1:1;/' **/*.[ch]

http: Preparse Retry-After header if response status is 503 or 3xx.

lib-http: Added support for creating CONNECT tunnels through HTTP.

lib-http: http-client: Made dummy response for returning internal errors more complete by filling in the version number and a proper date.

lib-http: Unified http-request.h and http-response.h headers. Renamed struct http_response_header to struct http_header_field, encapsulated the array in struct http_header and put it all in http-header.h/c Added inline utility functions for header querying and getting response/request payload size.

lib-http: Improved message header and body parsing for better RFC compliance. Added pre-parsed transfer-encoding and connection header content (array) to parsed message struct. Fixed message body handling for when both transfer-encoding and content-length headers are missing. Now duplicates of unique important message headers yield an error.

lib-http: Moved struct http_response* to http-response.h Also http-client.h now #includes only http-response.h