API: Improve form and tests for POST /batch/photos/edit endpoint #271

Signed-off-by: Michael Mayer <michael@photoprism.app>

internal/api/api_methods.go

@@ -0,0 +1,8 @@
+package api
+
+import (
+	"net/http"
+)
+
+// MethodsPutPost defines a string slice that contains the PUT and POST request methods.
+var MethodsPutPost = []string{http.MethodPut, http.MethodPost}