Add max-records argument to rt-validator

When run for an RT database with a large number of records that need to be
fixed, rt-validator can use large amounts of memory. On systems with less memory
this can cause oom errors.

Added a max-records argument to help lower memory usage.

sbin/rt-validator.in

@@ -76,6 +76,7 @@ Init(
     'verbose|v',
     'links-only',
     'cgm-only',
+    'max-records=i',
     'quiet',
 );
 
@@ -1410,6 +1411,10 @@ sub check_integrity {
 
     my $res = 1;
 
+    if ( $opt{'max-records'} ) {
+        $query .= " limit $opt{'max-records'}";
+    }
+
     my $sth = execute_query( $query, @binds );
     while ( my ($sid, @set) = $sth->fetchrow_array ) {
         $res = 0;