Purchase invoice item description too short

[dellermann]

If one save a purchase invoice that contains one or more items with a description larger than 255 characters the following occurs:

• the purchase invoice items are not stored
• the purchase invoice itself, however, is stored
• because the purchase invoice doesn't have items its getSubtotalNet() method produces an NPE

You should increase the size of the description field in table purchase_invoice_item.

[dellermann]

Fixed in commit 92db5a5bf072f06753b574efa2d08f74fac179d8.