generator:method=solar -> generator:source=solar (#620)

Author: Marc-marc-marc

data/deprecated.json

@@ -678,6 +678,10 @@
     "old": {"generator:source": "photovoltaic"},
     "replace": {"generator:source": "solar", "generator:method": "photovoltaic"}
   },
+  {
+    "old": {"generator:method": "solar"},
+    "replace": {"generator:source": "solar"}
+  },
   {
     "old": {"golf": "faiway"},
     "replace": {"golf": "fairway"}