more the logic of upload/update files more clear
change starred file item's width dynamically
Merge pull request #326 from haiwen/change_starred_file_item_width_dynamically

change starred file item's width dynamically
fix a bug where GetLinkReq triggers twice
apply minor improvements on the words of coments
add initial support for dropping file through repo tabs

- copy the dropped file to the worktree if the repository is synced
- add progressdialog for the mainwindow uploading
- don't bother the user if he (or she) cancels the uploading task
support encrypted repos now