* v2-idx-progress:
v2writable: show progress updates for index_sync
index: support --verbose option
v2writable: move index_sync options to sync state
v2writable: use prototypes for internal subs
v2writable: localize unindex-range.$EPOCH to $sync state
v2writable: move {ranges} into $sync state
v2writable: move {regen} into $sync state
v2writable: move {reindex} field to $sync state
v2writable: sync: move delete markers into $sync state
v2writable: introduce $sync state and put mm_tmp in it