MYOB AccountRight General Ledger export; fixed several issues

The following changes have been made to the "MYOB AccountRight" General Ledger export:

1. The "GST (BAS) Reporting" column was incorrectly exported as "GST/BAS Reporting".

1. The first line after the Header row should not be blank.

1. The "Journal Number" column is restricted to 8 characters, even though the specification notes it allows up to 255 characters. For Bank Transactions the Reference is now included in the Memo column and the Journal Number columns is either "B####" or "E####" (where #### is the Primary Key value) to denoted Bank Transaction or Bank Export respectively.

1. The "Is Credit" column was incorrect, showing "N" when should be "Y" and vice versa.