Added changes suggested by mbenshoof, michaeldg

- Fixed issue with dry run and preserve triggers
- Fixed issue with trim multiline
- Changed DSNParser in lib

bin/pt-online-schema-change

@@ -9554,7 +9554,9 @@ sub main {
          if ($orig_trigger ne '') {
             PTDEBUG && _d($orig_trigger);
             print $orig_trigger, "\n" if $o->get('print');
-            $cxn->dbh()->do($orig_trigger);
+            if ( $o->get('execute') ) {
+               $cxn->dbh()->do($orig_trigger);
+            }
          }
       }
    }
@@ -11108,7 +11110,7 @@ sub terminate_sql {
 sub trim {
    my ( $text ) = @_;
    die "I need a text argument" unless defined $text;
-   $text =~ s/^\s+|\s+$//gm;
+   $text =~ s/^\s+|\s+$//g;
    return $text;
 }
 

lib/DSNParser.pm

@@ -276,6 +276,7 @@ sub get_dbh {
       PrintError         => 0,
       ShowErrorStatement => 1,
       mysql_enable_utf8 => ($cxn_string =~ m/charset=utf8/i ? 1 : 0),
+      mysql_multi_statements => 1,
    };
    @{$defaults}{ keys %$opts } = values %$opts;
    if (delete $defaults->{L}) { # L for LOAD DATA LOCAL INFILE, our own extension