move old to legacy folder

.bzr/legacy/coder/topic/dynamic-programming/overview.json

@@ -0,0 +1,8 @@
+{
+    "title" : "Overview",
+    "slug" : "overview",
+    "content": [
+        {"data":"## Overview"},
+        {"data":"In this explore card, we're going to go over the basics of DP, provide you with a framework for solving DP problems, learn about common patterns, and walk through many examples.No prior knowledge of DP is required for this card, but you will need a solid understanding of recursion, a basic understanding of what greedy algorithms are, and general knowledge such as big O and hash tables. If you aren't familiar with recursion yet, check out the recursion explore card first."}
+    ]
+}