document web.ContentType* and web.APIError*

web/error.go

@@ -7,6 +7,7 @@ type HTTPError struct {
 	Data    interface{} `json:"data,omitempty" swaggerignore:"true"`
 }
 
+// Error strings used for HTTPError.Message.
 const (
 	APIErrorInvalidRequestFormat = "Invalid Request Format"
 	APIErrorInternalDatabase     = "Internal Database Error"

web/response.go

@@ -4,6 +4,7 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
+// MIME type strings.
 const (
 	ContentTypeJSON = "application/json"
 	ContentTypeJS   = "application/javascript"