Update required version of R. [ci skip]

paulnorthrop · paulnorthrop · commit e1b66903c0f7 · 2017-12-17T19:47:33.000Z
diff --git a/DESCRIPTION b/DESCRIPTION
@@ -25,7 +25,7 @@ Imports: graphics,
 License: GPL (>= 2)
 LazyData: TRUE
 Depends:
-    R (>= 3.3.1)
+    R (>= 3.4.1)
 RoxygenNote: 6.0.1
 Suggests: bang,
     inline,
