Add a workspace for the exercises

rust-exercises.code-workspace

@@ -0,0 +1,59 @@
+{
+    "folders": [
+        {
+            "path": "./minigrep"
+        },
+        {
+            "path": "./guessing_game"
+        },
+        {
+            "path": "./hottie"
+        },
+        {
+            "path": "./fibonacci"
+        },
+        {
+            "path": "./collections"
+        },
+        {
+            "path": "./restaurant"
+        },
+        {
+            "path": "./backyard"
+        },
+        {
+            "path": "./rectangles"
+        },
+        {
+            "path": "./subtractor"
+        },
+        {
+            "path": "./adder"
+        },
+        {
+            "path": "./functions"
+        },
+        {
+            "path": "./loops"
+        },
+        {
+            "path": "./panic"
+        },
+        {
+            "path": "./branches"
+        },
+        {
+            "path": "./variables"
+        },
+        {
+            "path": "./hello_cargo"
+        },
+        {
+            "path": "./hello_world"
+        },
+        {
+            "path": ".",
+            "name": "Solution Items"
+        }
+    ]
+}