create month-number-to-name function in utils package.

This is a helper function to convert '1' to 'January', for example. The intended
use for this is to work alongside the local-time package when generating the
month number from a timestamp.

src/utils.lisp

@@ -23,7 +23,8 @@
 	   #:create-timestamp-id
 	   #:format-filename
 	   #:format-keywords
-	   #:build-alert-string)
+	   #:build-alert-string
+           #:month-number-to-name)
   (:documentation "Utilities that do not depend on models."))
 
 (in-package #:utils)
@@ -166,3 +167,19 @@ to operate properly."
 	(second minute hour day month year)
       (get-decoded-time)
     (format nil "~d~2,'0d~d~2,'0d~2,'0d~2,'0d" year month day hour minute second)))
+
+(defun month-number-to-name (month-number)
+  "Converts `MONTHS-NUMBER' to its name (E.G. 1 to 'January')."
+  (cond ((= 1 month-number) "January")
+        ((= 2 month-number) "February")
+        ((= 3 month-number) "March")
+        ((= 4 month-number) "April")
+        ((= 5 month-number) "May")
+        ((= 6 month-number) "June")
+        ((= 7 month-number) "July")
+        ((= 8 month-number) "August")
+        ((= 9 month-number) "September")
+        ((= 10 month-number) "October")
+        ((= 11 month-number) "November")
+        ((= 12 month-number) "December")
+        (t nil)))