ztracker: add MR and MST

"Downloaded torrents must be seeded up to 0.8 OR 3 days of clean seed time."
http://ztracker.org/rules.php
Global MR is 0.6

src/Jackett.Common/Definitions/ztracker.yml

@@ -164,6 +164,11 @@ search:
       case:
         img[src="./pic/x2.gif"]: 2
         "*": 1
+    minimumratio:
+      text: 0.8
+    minimumseedtime:
+      # 3 days (as seconds = 3 x 24 x 60 x 60)
+      text: 259200
     date:
       selector: td:nth-child(2)
       remove: a, img