Added pattern migration guide to the change log

changelog/pattern-deprecate.dd

@@ -8,3 +8,57 @@ $(MREF std, regex) and $(MREF std, algorithm). They will be removed from
 $(MREF std, string) on May 2018.
 
 If you still need to use these, please see $(LINK2 https://github.com/dlang/undeaD, undeaD).
+
+The following are examples of the deprecated functions, and their modern replacements.
+
+Use $(REF find, std, algorithm, searching) to replace $(REF munch, std, string):
+-------
+import std.algorithm;
+import std.ascii;
+import std.string;
+import std.utf;
+
+string s = "\tabc";
+
+// old
+s.munch(whitespace);
+
+// new
+s = s.find!(a => !isWhite(a));
+-------
+
+Use $(REF matchFirst, std, regex) to replace $(REF inPattern, std, string):
+-------
+import std.string;
+import std.regex;
+
+// old
+if (inPattern('x', "a-z")) { ... }
+
+// new
+if ("x".matchFirst(regex("[a-z]"))) { ... }
+-------
+
+Use $(REF replaceAll, std, regex) to replace $(REF removechars, std, string):
+-------
+import std.string;
+import std.regex;
+
+// old
+"abc".removechars("a-z");
+
+// new
+"abc".replaceAll(regex("[a-z]"), "");
+-------
+
+Use $(REF uniq, std, algorithm, iteration) to replace $(REF squeeze, std, string):
+-------
+import std.algorithm;
+import std.string;
+
+// old
+"hello".squeeze;
+
+// new
+"hello".uniq;
+-------