Investigate SFTP for upload

Hart came up with some suggestions

SFTP
allow district to create unix users users with district id
sims interface for creating account/changing password
write only directory
http://stackoverflow.com/questions/511463/monitor-directory-for-cha...
email will be sent to district_upload user

inotify or 5 or 10 min cronjob to poll upload directory

As of right now, I'm roughly done with the ruby script that will be executed by a cron job to walk through all the subdirectories (each associated with a district admin) in the sftp receipt directory, and move all successfully transferred files into another directory from which they will be processed. After I get ProFTPd (or another SFTP server) configured on a virtual machine, I'm going to test it to make sure it's tolerant to different kinds of connection loss while receiving a file. After that, the only remaining challenge will be to associate the usernames with their own UNIX accounts so that the SIMS application can determine which files were uploaded by which users when processing.