8.6.1

• fix mmap window new/free cycling
• fix some compiler warnings
• remove the 64-image limit on bandary operations
• better version date [bmwiedemann]
• bump wrapper script version [bgilbert]
• fix a memleak on error during jpeg buffer write [lovell]
• fix misspelling of IPTC as IPCT [lovell]
• seq could be set on small images opened in random-access mode [aferrero2707]
• fix small memleak in dzsave [lovell]
• small speedup for rgb->g [lovell]