Improve a bit the Octopress thingy

- Octopress implies Jekyll
- Octopress can have a `meta` named "generator"
- The `html` section is now moregeneric

src/apps.json

@@ -5040,9 +5040,14 @@
 		},
 		"Octopress": {
 			"cats": [
+				1,
 				11
 			],
-			"html": "Powered by <a href=\"http://octopress.org\">Octopress",
+			"html": "Powered by <a href=\"http://octopress.org\">",
+			"implies": "Jekyll",
+			"meta": {
+				"generator": "Octopress"
+			},
 			"icon": "octopress.png",
 			"website": "octopress.org"
 		},