Update examples project to 2018.4.18f1 (#3618)

From 2018.4.14f1.  An internal package dependency was updated as
a side effect.

Project/Packages/manifest.json

 {
   "dependencies": {
     "com.unity.ads": "2.0.8",
-    "com.unity.analytics": "3.2.2",
+    "com.unity.analytics": "3.2.3",
     "com.unity.collab-proxy": "1.2.15",
     "com.unity.ml-agents": "file:../../com.unity.ml-agents",
     "com.unity.package-manager-ui": "2.0.8",
     "com.unity.modules.wind": "1.0.0",
     "com.unity.modules.xr": "1.0.0"
   },
-  "testables" : [
+  "testables": [
     "com.unity.ml-agents"
   ]
 }

Project/ProjectSettings/ProjectVersion.txt

-m_EditorVersion: 2018.4.14f1
+m_EditorVersion: 2018.4.18f1

com.unity.ml-agents/CHANGELOG.md

  - Fixed an issue when using GAIL with less than `batch_size` number of demonstrations. (#3591)
  - The interfaces to the `SideChannel` classes (on C# and python) have changed to use new  `IncomingMessage` and `OutgoingMessage` classes. These should make reading and writing data to the channel easier. (#3596)
  - Updated the ExpertPyramid.demo example demonstration file (#3613)
+ - Updated project version for example environments to 2018.4.18f1 (#3618)
 
 ## [0.14.1-preview] - 2020-02-25