added user interfaces and utilities that enable experiment data download from machines that have ssh access to the storage host

introduced interface for notifying ds service to update experiment users; fix bug in linux experiment utility

add file processing interfaces; rename storage manager to experiment manager; add ability to manage groups/file permissions

add first functional DS web service with user, experiment and auth controllers that allow retrieving user and experiment information from the db, start/stop experiment, and principal authorization; added corresponding API and CLI classes; added storage manager skeleton