Merge branch...

Merge branch 'ddmr_indexed_mode_mark_all_read_updates_and_newscan_force_indexed_menu_opts' into 'master'

DDMsgReader: Updated behavior for indexed menu R (mark all read) when doing a newscan. Ctrl-S does scan refresh in indexed menu. New R "snap-to" option for the indexed menu. Also, command-line options for forcing use of the indexed mode menu when doing a

See merge request !387