- (WGI|WSF)_RESPONSE(*) renamed write_headers_string as write_header_text

- HTTP_HEADER.string does not have the ending CRLFCRLF .. but just CRLF
- WGI_RESPONSE.write_header_text has the responsibility to handle the last blank line CRLF (separating the header from the message)
- HTTP_HEADER.string does not set anymore a default content type as text/html
- added WGI_RESPONSE.write_header_lines (ITERABLE [TUPLE [name,value: READABLE_STRING_8]] mainly as an helper method,
   this way the WGI user does not have to know about the CRLF end of line

library/server/ewsgi/src/helper/wgi_response_stream.e

@@ -75,12 +75,31 @@ feature -- Status setting
 
 feature -- Header output operation		
 
-	write_headers (a_headers: READABLE_STRING_8)
+	write_header_text (a_text: READABLE_STRING_8)
 		do
-			write (a_headers)
+			write (a_text)
+			write (crlf)
 			header_committed := True
 		end
 
+	write_header_lines (a_lines: ITERABLE [TUPLE [name: READABLE_STRING_8; value: READABLE_STRING_8]])
+		local
+			h: STRING_8
+		do
+			create h.make (256)
+			across
+				a_lines as c
+			loop
+				h.append (c.item.name)
+				h.append_character (':')
+				h.append_character (' ')
+				h.append (c.item.value)
+				h.append_character ('%R')
+				h.append_character ('%N')
+			end
+			write_header_text (h)
+		end
+
 feature -- Output operation
 
 	write_string (s: READABLE_STRING_8)
@@ -109,6 +128,9 @@ feature -- Output operation
 
 feature {NONE} -- Implementation: Access
 
+	crlf: STRING = "%R%N"
+			-- End of header
+
 	output: WGI_OUTPUT_STREAM
 			-- Server output channel