refactor(spacing): generate spacing atomic classes programatically

docs/_data/position.json

@@ -0,0 +1,42 @@
+{
+  "values": "0, 1px, 2px, 4px, 6px, 8px, 12px, 16px, 24px, 32px, 48px, 64px, 96px, 128px, 50%, 100%",
+  "properties": "t, r, b, l, i",
+  "definitions": [
+    {
+      "term": "t",
+      "define": "top"
+    },
+    {
+      "term": "r",
+      "define": "right"
+    },
+    {
+      "term": "b",
+      "define": "bottom"
+    },
+    {
+      "term": "l",
+      "define": "left"
+    },
+    {
+      "term": "i",
+      "define": "inset"
+    },
+    {
+      "term": "tn",
+      "define": "negative top"
+    },
+    {
+      "term": "rn",
+      "define": "negative right"
+    },
+    {
+      "term": "bn",
+      "define": "negative bottom"
+    },
+    {
+      "term": "ln",
+      "define": "negative left"
+    }
+  ]
+}