Second attempt to fix version warning banner (#1010)

Author: scaramallion

docs/_static/switcher.json

@@ -1,53 +1,53 @@
 [
   {
     "name": "dev",
-    "version": "3.1.0",
+    "version": "3.1.0.dev0",
     "url": "https://pydicom.github.io/pynetdicom/dev/"
   },
   {
-    "name": "3.0.0 (stable)",
-    "version": "v3.0.0",
+    "name": "3.0 (stable)",
+    "version": "3.0.0",
     "url": "https://pydicom.github.io/pynetdicom/stable/",
     "preferred": true
   },
   {
-    "name": "2.1.1",
-    "version": "v2.1.1",
+    "name": "2.1",
+    "version": "2.1.1",
     "url": "https://pydicom.github.io/pynetdicom/2.1/"
   },
   {
-    "name": "2.0.3",
-    "version": "v2.0.3",
+    "name": "2.0",
+    "version": "2.0.3",
     "url": "https://pydicom.github.io/pynetdicom/2.0/"
   },
   {
-    "name": "1.5.7",
-    "version": "v1.5.7",
+    "name": "1.5",
+    "version": "1.5.7",
     "url": "https://pydicom.github.io/pynetdicom/1.5/"
   },
   {
-    "name": "1.4.1",
-    "version": "v1.4.1",
+    "name": "1.4",
+    "version": "1.4.1",
     "url": "https://pydicom.github.io/pynetdicom/1.4/"
   },
   {
-    "name": "1.3.1",
-    "version": "v1.3.1",
+    "name": "1.3",
+    "version": "1.3.1",
     "url": "https://pydicom.github.io/pynetdicom/1.3/"
   },
   {
-    "name": "1.2.0",
-    "version": "v1.2.0",
+    "name": "1.2",
+    "version": "1.2.0",
     "url": "https://pydicom.github.io/pynetdicom/1.2/"
   },
   {
-    "name": "1.1.0",
-    "version": "v1.1.0",
+    "name": "1.1",
+    "version": "1.1.0",
     "url": "https://pydicom.github.io/pynetdicom/1.1/"
   },
   {
-    "name": "1.0.0",
-    "version": "v1.0.0",
+    "name": "1.0",
+    "version": "1.0.0",
     "url": "https://pydicom.github.io/pynetdicom/1.0/"
   }
 ]