RectangleObject import missing & file handling workaround

[sebastian-e-dox]

I use pyPdf with Python 3.2 on my Windows machine and just got some errors I could resolve:

first one was the opening of a PDF file with the PdfFileReader. I used the code

 file = open("PATH_WITH_FILE_AND_EXTENSION", "rb")
 doc = PdfFileReader(file)```

The second thing I discovered was that the pdf.py misses the RectangleObject import from the generic.py file. So just add it.