Sync - async checksum calculation when processing modified files
FSM fix in JobListProxy

JobListProxy - do_finish can return done, so need handle this and return done from get_task
FSM fix in JobIteratorProxy - never return done from do_finish.

We can't return 'done' from do_finish cause job is done only when itterator returns false
Sync command - detect options implementation

1) handle --detect properly
2) thus upload/delete without treehash check implemented