Update seafile-admin

Remove new line character (if exists). Also Python 2.7.8 added a new line character with read() resulting data dir not being recognized as directory.
correct English
Merge pull request #779 from chtfn/patch-1

correct English
Merge pull request #776 from dbruenig/master

Remove new line characters from seafile_data_dir variable
Merge pull request #1 from haiwen/master

pull request from master