slaprunner: ...

Yet another non-obvious change that was committed without explanation.
Let's revert and see what breaks...

software/slaprunner/software.cfg

@@ -152,7 +152,6 @@ eggs =
   slapos.recipe.build
   slapos.toolbox[flask_auth]
   gunicorn==19.7.1
-  futures
   ${slapos-cookbook:eggs}
   slapos.core # listed explicitly for scripts generation
 
@@ -165,7 +164,6 @@ eggs +=
 [versions]
 Flask-Auth = 0.85
 cns.recipe.symlink = 0.2.3
-futures = 3.0.5
 gitdb = 0.6.4
 gunicorn = 19.7.1
 prettytable = 0.7.2