Implement namespace CRUD + various small fixes

Other fixes and improvements:
 - add parseISODateWithErr and parseISODatePtrWithErr handlers for incoming data
 - add service & repository errors
 - cleanup old (unbound) attachment controllers from router
 - fix system repository error prefix (auth => system)

codegen/codegen.php

@@ -101,6 +101,8 @@ $parsers = array(
 	"int" => "parseInt",
 	"uint" => "parseUint",
 	"bool" => "parseBool",
+	"time.Time" => "parseISODateWithErr",
+	"*time.Time" => "parseISODatePtrWithErr",
 	"sqlxTypes.JSONText" => "parseJSONTextWithErr",
 );