Multiple pdfs

[bengolder]

Changes:

• combine pdfs into one
• submit n answers, get n filled forms, using .fill_many() method

[bengolder]

It looks like recent attempts to install pdftk on Travis are failing. It is unclear why. I'm going to try pushing inconsequential changes in order to trigger new builds. Hopefully it was a temporary connectivity issue on Travis's side.

$ sudo apt-get install pdftk -y
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package pdftk
The command "sudo apt-get install pdftk -y" failed and exited with 100 during .
Your build has been stopped.

[coveralls]

Coverage increased (+0.8%) to 84.416% when pulling d04d9adf9adda7a906935a33e5ec426e08262b35 on test_pdftk into 3fc9213805c6cddfc9d8a4d0d12b90981cbc7d04 on master.

[bengolder]

I'm going to assume Travis was having temporary problems. Merging.