fix sourcing of remote files

Summary:
Remote files (from s3) cannot be sourced as scripts
Had to use same solution as in ka_hive_init - add file and use local path
It isn't perfect but I don't think there's other solution

Test Plan: student_teacher_count.q does not produce "is not a file error"

Reviewers: jace

Reviewed By: jace

Differential Revision: http://phabricator.khanacademy.org/D2595