Add docs requirements file

docs/requirements.txt

@@ -0,0 +1,21 @@
+sphinxcontrib-napoleon
+sphinxcontrib-autoprogram==0.1.2
+isort
+paramiko>=1.15.2
+mako>=1.0.0
+pyelftools>=0.2.3
+capstone
+ropgadget>=5.3
+pyserial>=2.7
+requests>=2.5.1
+pip>=6.0.8
+tox>=1.8.1
+pygments>=2.0
+sphinx_rtd_theme
+doc2dash
+coveralls
+pycparser
+psutil>=3.1.0
+python-ptrace>=0.8
+six
+future