need to comment out another thumbnail check due to build test environment not having libjpeg installed

css_click will try clicking multiple times.

disable assertions on thumbnail generation as it puts a system requirement on libjpeg which may not be installed on the test machines

and code reorganization

allow for an optional throw_on_not_found on contentstore().find() so we can clean up caller logic in the tests

A few notes:
1. Downloads are done through direct requests.  This is due to the difficulty of downloading a file to the correct place
2. Modifiying a file will just change the file to a random 10 character string.
3. The page is reloaded in between uploads.  This is due to a current caching bug that is in the process of being looked into and will be updated once it is fixed.

% to format
css_find().click() to its actual function
A few name changes as well as step changes
Removal of drag testing
A refactoring of login and create user.  Login will no longer create the specified user

Also added in drag and drop helper.  Please be careful using this method as it is truly a hack to obtain the visual effects.  As of this commit, selenium does not support drag and drop for jQuery sortable items

Seems like on chrome when cancel is hit in the file chooser, the 'changed' event is fired and startUpload() was being called. We need to check to see if the upload file is blank and - if so - just return immediately out of the function

TODO: When deleting is available, test deleting uploaded files`

attempt to test xmodule_modified (see fixme)
Removed obsolete else clause from before conversion
Ensure factories use datetime not struct_time for start date
Added more unit tests for settings encoder

Also modified the create_course method in common to allow for the possibility to access the course name and etc. from other files.