feature/syncdb-noinput

This PR just fixes an issue that occurs in the `create-virtualenv` step of the `vagrant up` process when it runs the `manage.py syncdb` command. It modifies the command so that it uses the `--noinput` to suppress user prompts. 

Here's the error I get when this flag is not used:

```bash
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating tables ...
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table auth_permission
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table auth_group_permissions
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table auth_group
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table auth_user_groups
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table auth_user_user_permissions
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table auth_user
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table django_content_type
notice: /Stage[main]//Exec[create-virtualenv]/returns: Creating table django_session
notice: /Stage[main]//Exec[create-virtualenv]/returns: 
notice: /Stage[main]//Exec[create-virtualenv]/returns: You just installed Django's auth system, which means you don't have any superusers defined.
notice: /Stage[main]//Exec[create-virtualenv]/returns: Would you like to create one now? (yes/no): Traceback (most recent call last):
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "manage.py", line 10, in <module>
notice: /Stage[main]//Exec[create-virtualenv]/returns:     execute_from_command_line(sys.argv)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 399, in execute_from_command_line
notice: /Stage[main]//Exec[create-virtualenv]/returns:     utility.execute()
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 392, in execute
notice: /Stage[main]//Exec[create-virtualenv]/returns:     self.fetch_command(subcommand).run_from_argv(self.argv)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/core/management/base.py", line 242, in run_from_argv
notice: /Stage[main]//Exec[create-virtualenv]/returns:     self.execute(*args, **options.__dict__)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/core/management/base.py", line 285, in execute
notice: /Stage[main]//Exec[create-virtualenv]/returns:     output = self.handle(*args, **options)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/core/management/base.py", line 415, in handle
notice: /Stage[main]//Exec[create-virtualenv]/returns:     return self.handle_noargs(**options)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/core/management/commands/syncdb.py", line 112, in handle_noargs
notice: /Stage[main]//Exec[create-virtualenv]/returns:     emit_post_sync_signal(created_models, verbosity, interactive, db)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/core/management/sql.py", line 216, in emit_post_sync_signal
notice: /Stage[main]//Exec[create-virtualenv]/returns:     interactive=interactive, db=db)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/dispatch/dispatcher.py", line 185, in send
notice: /Stage[main]//Exec[create-virtualenv]/returns:     response = receiver(signal=self, sender=sender, **named)
notice: /Stage[main]//Exec[create-virtualenv]/returns:   File "/home/vagrant/.virtualenvs/lti_sandbox/local/lib/python2.7/site-packages/django/contrib/auth/management/__init__.py", line 120, in create_superuser
notice: /Stage[main]//Exec[create-virtualenv]/returns:     confirm = input(msg)
notice: /Stage[main]//Exec[create-virtualenv]/returns: EOFError: EOF when reading a line
err: /Stage[main]//Exec[create-virtualenv]/returns: change from notrun to 0 failed: /vagrant/vagrant/venv_bootstrap.sh returned 1 instead of one of [0] at /tmp/vagrant-puppet/manifests/default.pp:222
notice: /Stage[main]//File[/home/vagrant/.bash_profile]: Dependency Exec[create-virtualenv] has failures: true
warning: /Stage[main]//File[/home/vagrant/.bash_profile]: Skipping because of failed dependencies

```

@cmurtaugh Can you review and merge if this is OK?