Added assembly definition files for better control over how the code …

…is compiled.

To do this I had to split the editor and runtime code more cleanly which meant moving GlobalDisplaySettings.cs to the Editor folder. I also renamed the "Scripts" folder to "Runtime" as I think it more clearly describes what type of code it holds.

PathCreator/Core/Editor/PathCreatorEditor.asmdef

@@ -0,0 +1,16 @@
+{
+    "name": "PathCreatorEditor",
+    "references": [
+        "PathCreator"
+    ],
+    "optionalUnityReferences": [],
+    "includePlatforms": [
+        "Editor"
+    ],
+    "excludePlatforms": [],
+    "allowUnsafeCode": false,
+    "overrideReferences": false,
+    "precompiledReferences": [],
+    "autoReferenced": true,
+    "defineConstraints": []
+}

PathCreator/Core/Runtime/PathCreator.asmdef

@@ -0,0 +1,3 @@
+{
+	"name": "PathCreator"
+}