开始迁移到第二版的ffbackup协议
修正目录遍历结果不正确的bug
add is_project_name_safe()
only call chdir() at server.cpp
完成start_backup
add send_addition
debug info
add finish_backup
initial_event changed to FF_ON_WRITE
add send_deletion
do not forget to response to client when done
add namespace ff_sched
add ffstorage::hash_sha1()
add FF_ON_TIMEOUT and ffprotocol::get_hash(_task)
delete -> delete[]
fix bug: do not write data after timeout
add get_file_size() in helper.cpp and helper.h
add rsync_sig() in ffstorage
add class get_signature