Revert "Update gem bundle for Jekyll 3.2" (#1435)

This reverts commit 61b62e3.

Author: hsbt

Gemfile.lock

@@ -1,17 +1,15 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    colorator (1.1.0)
+    colorator (0.1)
     ffi (1.9.14)
-    forwardable-extended (2.6.0)
-    jekyll (3.2.0)
-      colorator (~> 1.0)
+    jekyll (3.1.6)
+      colorator (~> 0.1)
       jekyll-sass-converter (~> 1.0)
       jekyll-watch (~> 1.1)
       kramdown (~> 1.3)
       liquid (~> 3.0)
       mercenary (~> 0.3.3)
-      pathutil (~> 0.9)
       rouge (~> 1.7)
       safe_yaml (~> 1.0)
     jekyll-sass-converter (1.4.0)
@@ -34,8 +32,6 @@ GEM
       mini_portile2 (~> 2.1.0)
       pkg-config (~> 1.1.7)
     paint (0.9.0)
-    pathutil (0.14.0)
-      forwardable-extended (~> 2.6)
     pkg-config (1.1.7)
     rack (1.6.4)
     rack-protection (1.5.3)