Update python dependencies

Change-Id: Ic1ba3152160e9255d14ae66881e452a99930b0d8
diff --git a/nlsr/debian/control b/nlsr/debian/control
index cf63d0e..69763e7 100644
--- a/nlsr/debian/control
+++ b/nlsr/debian/control
@@ -2,13 +2,13 @@
 Priority: extra
 Maintainer: Ashlesh Gawande <agawande@memphis.edu>
 Build-Depends: debhelper (>= 9.20160709),
- python3 (>= 3.5.0),
+ python3 (>= 3.6.0),
  pkg-config (>= 0.26),
  libndn-cxx-dev (>= 0.8.0),
  libchronosync-dev (>= 0.5.4),
  libpsync-dev (>= 0.3.0),
  libboost-all-dev (>= 1.58.0),
- python3-sphinx (>= 1.1.3),
+ python3-sphinx (>= 1.6.0),
  git
 Standards-Version: 4.5.0
 Section: net