snapshot: add latest as version if not specified
import: fix issue caused by variable expansion
append version with snapshot_id_add_version() instead of if+snapshot_id_has_version()
snapshot: snapshot existing snapshot without cloning
import: fix import & snapshot scenario
run: refactoring
remove: call dataset_destroy() instead of execute zfs command directly
move: rename to rename
rename: rename with snapshot_rename instead of dataset_move because -p causes problem
rename subcommand: remove debug flag
add export command