Create "generic" bid sheets and control forms

[chmarr]

Create generic versions of these forms and include those in the "artshow" application. Construct in such a way that if a show can create their own forms with the spaces in the same locations, the "pdf printing" module wont need to be updated.

Also include "piece identification", "file folder", "file folder with extra info" and "mailing label" PDFs, since these are already very generic.