Add python-qwt5-qt4 as dep?

[devnulling]

From: gnuradio/gnuradio#1518

In Ubuntu 16.04 I installed GNURadio using pybombs. The Filter Design Tool didn't open either. Running the script from the command line, I got the error
user@pc:~/src/gnuradio/default$ python ./lib/python2.7/dist-packages/gnuradio/filter/filter_design.py
Please install PyQwt5 to run this script (http://pyqwt.sourceforge.net/)
user@pc: sudo apt install python-qwt5-qt4
Solved the problem and the tool starts from command line and GNU Radio Companion (version 3.7.12git-361-g713629cc)
I guess that the pybomb recipe needs to add python-qwt5-qt4 as a dependency?