share/config/default.ezsync: change comment of `Conflict Strategy' setting; conflict strategy = quit; change comment of  `User Confirmed Operation' setting
share/commands/commit: implement user confirmation; optimize verbose mode; update local index in the last stage
share/commands/sort-hash-list: add option k: do not remove duplicated files, keep them
share/commands/generate-tree-graph: the output ps file name set to `head.ps'
add share/commands/transfer-global-index
add share/commands/merge