Added the possibility to provide the sendmail location in NOTIFICATION_SENDMAIL_MAILER.

Added NOTIFICATION_STORAGE_MAILER which allow to store the email in a storage (could be just output, file, database ...)
Added SMTP implementation, based on EiffelNet SMTP_PROTOCOL.
   note: it is possible to exclude this by setting ecf variable "smtp_notification_email_disabled" to "True"
   this way help to manage dependencies, since the Eiffel Net library would not be included neither.
Fixed Date header value computation.

library/runtime/process/notification_email/storage/notification_email_file_storage.e

@@ -0,0 +1,74 @@
+note
+	description: "Store email in specific file (could also be stderr, ...)."
+	date: "$Date: 2015-06-30 15:49:56 +0200 (mar., 30 juin 2015) $"
+	revision: "$Revision: 97588 $"
+
+class
+	NOTIFICATION_EMAIL_FILE_STORAGE
+
+inherit
+	NOTIFICATION_EMAIL_STORAGE
+
+create
+	make
+
+feature {NONE} -- Initialization
+
+	make (a_output_file: FILE)
+		require
+			a_output_file_valid: a_output_file.exists
+		do
+			output := a_output_file
+		end
+
+	output: FILE
+
+feature -- Status report
+
+	is_available: BOOLEAN
+			-- Is associated storage available?
+		do
+			Result := output.exists and output.is_access_writable
+		end
+
+	has_error: BOOLEAN
+			-- Last operation reported an error?
+
+feature -- Storage
+
+	put (a_email: NOTIFICATION_EMAIL)
+			-- Store `a_email'.
+		local
+			retried: BOOLEAN
+			l_close_needed: BOOLEAN
+		do
+			if not retried then
+				has_error := False
+				if not output.is_open_write then
+					output.open_write
+					l_close_needed := True
+				end
+				output.put_string ("%N----%N" + a_email.message)
+				if l_close_needed then
+					output.close
+				else
+					output.flush
+				end
+			end
+		rescue
+			retried := True
+			has_error := True
+			retry
+		end
+
+;note
+	copyright: "2011-2015, Jocelyn Fiat, Javier Velilla, Olivier Ligot, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+	source: "[
+			Eiffel Software
+			5949 Hollister Ave., Goleta, CA 93117 USA
+			Telephone 805-685-1006, Fax 805-685-6869
+			Website http://www.eiffel.com
+			Customer support http://support.eiffel.com
+		]"
+end

library/runtime/process/notification_email/storage/notification_email_storage.e

@@ -0,0 +1,38 @@
+note
+	description: "Abtract interface of email storage."
+	date: "$Date: 2015-06-30 15:49:56 +0200 (mar., 30 juin 2015) $"
+	revision: "$Revision: 97588 $"
+
+deferred class
+	NOTIFICATION_EMAIL_STORAGE
+
+feature -- Status report
+
+	is_available: BOOLEAN
+			-- Is associated storage available?
+		deferred
+		end
+
+	has_error: BOOLEAN
+			-- Last operation reported an error?
+		deferred
+		end
+
+feature -- Storage
+
+	put (a_email: NOTIFICATION_EMAIL)
+			-- Store `a_email'.
+		deferred
+		end
+
+note
+	copyright: "2011-2015, Jocelyn Fiat, Javier Velilla, Olivier Ligot, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+	source: "[
+			Eiffel Software
+			5949 Hollister Ave., Goleta, CA 93117 USA
+			Telephone 805-685-1006, Fax 805-685-6869
+			Website http://www.eiffel.com
+			Customer support http://support.eiffel.com
+		]"
+end