Add release notes

Author: Bryan

docs/content/releases/4.1.1.md

@@ -0,0 +1,18 @@
+**Refactor price formatting and parsing. As a result, breaking changes may have been introduced.**
+
+* The price format function has refactored.
+  * Function signature is unchanged.
+  * Function behavior has changed.
+    * A string is always returned.
+    * Passing a non-numeric value will yield a zero-length string.
+    * Passing an invalid unit code will yield a zero-length string.
+* The price parse function has been refactored.
+  * Function signature was expanded.
+    * New arguments were appended. The same values used to format a value should be used when parsing.
+      * fractionSeparator
+      * specialFractions
+      * thousandsSeparator
+  * Function behavior has changed.
+    * Passing a value which cannot will yield Number.NaN.
+    * Passing an invalid unit code will yield Number.NaN.
+* A formal enumeration, called UnitCode, was added.