Update some dates

contents.json

@@ -1349,7 +1349,7 @@
       "screenshots": [
         "https://raw.githubusercontent.com/aslanyanhaik/Quick-Chat/master/screenshot.gif"
       ],
-      "date_added": "Wed Jan 06 2017",
+      "date_added": "Jan 06 2017",
       "suggested_by": "@aslanyanhaik",
       "stars": 1662,
       "license": "mit"
@@ -1421,7 +1421,7 @@
       "screenshots": [
         "https://github.com/surayashivji/potter-pics/blob/master/Overview.gif"
       ],
-      "date_added": "Sun Jan 15 2017",
+      "date_added": "Jan 15 2017",
       "suggested_by": "@surayashivji",
       "stars": 140
     },
@@ -3215,7 +3215,7 @@
       "tags": [
         "swift"
       ],
-      "date_added": "Aug 19th 2016",
+      "date_added": "Aug 19 2016",
       "suggested_by": "@caleb0",
       "stars": 18
     },
@@ -3234,7 +3234,7 @@
       "tags": [
         "swift"
       ],
-      "date_added": "August 31th 2017",
+      "date_added": "Aug 31 2017",
       "suggested_by": "@pixel16",
       "stars": 45
     },
@@ -10706,7 +10706,7 @@
       "tags": [
         "swift"
       ],
-      "date_added": "Apr 2 2018 +0800",
+      "date_added": "Apr 2 2018",
       "suggested_by": "@ethanhuang13",
       "stars": 102,
       "lang": "zho",
@@ -14785,7 +14785,7 @@
         "https://i.imgur.com/MdQJiLj.png"
       ],
       "license": "mit",
-      "date_added": "2018-03-18T15:16:43+01:00",
+      "date_added": "Mar 18 2018",
       "suggested_by": "@erikmartens",
       "stars": 88
     },
@@ -18135,7 +18135,7 @@
         "https://is1-ssl.mzstatic.com/image/thumb/Purple113/v4/89/fe/33/89fe3374-808d-7583-b4de-ec24198506a1/mzl.xdysdjdb.png/460x0w.jpg"
       ],
       "license": "agpl-3.0",
-      "date_added": "Thu Sept 5 2019",
+      "date_added": "Sep 5 2019",
       "suggested_by": "@strongbox-password-safe",
       "stars": 371
     },