Release v6.4.7

• [fix] sales order status for maintenance
• [minor] [typo]
• [fix][patch] Delete duplicate bins
• [fix] set title in Journal Entry only if not set
• [fix] [minor] collapsible section for Item - removed custom script
• [fix] get_party_details.js - set posting_date if args are initialised
• [minor] [fix] Use customer_name in Sales Analytics
• [fix] get allocated_percentage from party's sales team
• [fix] [minor] stock_entry.py error for None qty
• [fix] Added Letter Head field to Purchase Invoice
• [fix] copy task titles with project
• [fix] Field type of Age field converted to Int
• minor fix, escape % char
• [fix] Multiple minor fixes
• [fix] sales order notification