Bug 9669 - Replace YUI buttons on staff client cart toolbar

Bug 9669 - Replace YUI buttons on staff client cart toolbar

This patch converts the toolbar on the staff client cart
page to Bootstrap, replacing YUI button code with Bootstrap markup.

To test, view the staff client cart and confirm that all buttons look
correct and work correctly. Functions to test include:

Full/brief display
Send
Download (various options)
Print
Empty and close
Hide window

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Comment: Tested all buttons, works very well. No errors
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>