Allow zebra search for Accelerated Reading Level in field 526$c

Signed-off-by: Galen Charlton <gmcharlt@gmail.com>

etc/zebradb/biblios/etc/bib1.att

@@ -186,4 +186,5 @@ att 9900    Author-personal-bibliography
 att 9902    Author-in-order
 # Lexile number
 att 9903    lex
+att 9904    arl
 att 9520    Item

etc/zebradb/ccl.properties

@@ -1034,6 +1034,9 @@ Illustration-code 1=Illustration-code
 # Lexile Number
 lex 1=9903 r=r
 
+#Accelerated Reader Level
+arl 1=9904 r=r
+
 ## Statuses
 popularity 1=issues
 

etc/zebradb/marc_defs/marc21/biblios/record.abs

@@ -148,6 +148,7 @@ melm 505        Note:w,Note:p
 melm 510        Indexed-by
 melm 520        Abstract:w,Abstract:p
 melm 521$a      lex:n
+melm 526$c      arl,arl:n
 #melm 533$d     pubdate,pubdate:s
 #melm 541$d     Date-of-acquisition,Date-of-acquisition:s
 melm 590        Note:w,Note:p