Allow export to pdf for custom forms within documents

[#1]

As part of our document approval process we have custom forms that key stakeholders must complete for sign off purposes. We need to get copies of these forms for our job bags, At the moment the export to pdf function is available for projects etc but not for within the documents section which means were having to take lost of screen shots of all the information we need. Can you please add in the export to pdf function for the documents section too?