Implemented WSF_RESPONSE.put_error (...) and related

Added WSF_RESPONSE.put_character
Renamed  WGI_OUTPUT_STREAM.put_character_8 as put_character  to follow style of put_string  (and not put_string_8)
Refactored the WSF_DEFAULT_SERVICE_LAUNCHER
Added WSF_DEFAULT_SERVICE to be more user friendly
Splitted the wsf/default/ libraries to have wsf/connector/... and being able to handle more than one connector in the same application

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

@@ -17,9 +17,10 @@ create
 
 feature {NONE} -- Initialization
 
-	make (a_output: like output)
+	make (a_output: like output; a_error: like error)
 		do
 			output := a_output
+			error := a_error
 		end
 
 feature {WGI_CONNECTOR, WGI_SERVICE} -- Commit
@@ -97,6 +98,12 @@ feature -- Header output operation
 
 feature -- Output operation
 
+	put_character (c: CHARACTER_8)
+			-- Send the character `c'
+		do
+			output.put_character (c)
+		end
+
 	put_string (s: READABLE_STRING_8)
 			-- Send the string `s'
 		do
@@ -115,11 +122,25 @@ feature -- Output operation
 			output.flush
 		end
 
+feature -- Error reporting
+
+	put_error (a_message: READABLE_STRING_8)
+			-- Report error described by `a_message'
+			-- This might be used by the underlying connector
+		do
+			if attached error as err then
+				err.put_error (a_message)
+			end
+		end
+
 feature {NONE} -- Implementation: Access
 
 	output: WGI_OUTPUT_STREAM
 			-- Server output channel
 
+	error: detachable WGI_ERROR_STREAM
+			-- Server output channel
+
 ;note
 	copyright: "2011-2012, Jocelyn Fiat, Javier Velilla, Eiffel Software and others"
 	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"