Spell out evdev dependency for readthedocs

Author: ddemidov

docs/conf.py

@@ -26,6 +26,7 @@
     import pip
     pip.main(['install', 'sphinx_bootstrap_theme'])
     pip.main(['install', 'recommonmark'])
+    pip.main(['install', 'evdev'])
 
 import sphinx_bootstrap_theme
 from recommonmark.parser import CommonMarkParser