Revert "only build linux"

This reverts commit 3d79e1f.

Author: StephenHodgson

.github/workflows/build-options.json

@@ -1,8 +1,12 @@
 {
   "os": [
-    "ubuntu-latest"
+    "ubuntu-latest",
+    "windows-latest",
+    "macos-latest"
   ],
   "unity-version": [
+    "4.7.2",
+    "5.6.7f1 (e80cc3114ac1)",
     "2017.4.40f1",
     "2018",
     "2019.x",
@@ -30,6 +34,59 @@
     {
       "os": "ubuntu-latest",
       "build-target": "Android"
+    },
+    {
+      "os": "windows-latest",
+      "unity-version": "none"
+    },
+    {
+      "os": "windows-latest",
+      "build-target": "StandaloneWindows64"
+    },
+    {
+      "os": "macos-latest",
+      "unity-version": "none"
+    },
+    {
+      "os": "windows-latest",
+      "build-target": "Android"
+    },
+    {
+      "os": "macos-latest",
+      "build-target": "StandaloneOSX"
+    },
+    {
+      "os": "macos-latest",
+      "build-target": "iOS"
+    }
+  ],
+  "exclude": [
+    {
+      "os": "ubuntu-latest",
+      "unity-version": "4.7.2"
+    },
+    {
+      "os": "macos-latest",
+      "unity-version": "4.7.2"
+    },
+    {
+      "os": "windows-latest",
+      "build-target": "Android",
+      "unity-version": "4.7.2"
+    },
+    {
+      "os": "ubuntu-latest",
+      "unity-version": "5.6.7f1 (e80cc3114ac1)"
+    },
+    {
+      "os": "macos-latest",
+      "build-target": "iOS",
+      "unity-version": "5.6.7f1 (e80cc3114ac1)"
+    },
+    {
+      "os": "windows-latest",
+      "build-target": "Android",
+      "unity-version": "5.6.7f1 (e80cc3114ac1)"
     }
   ]
 }