Update gem file to build in docker container locally.

Author: insectengine

Diff for: Gemfile

@@ -33,3 +33,5 @@ gem "tzinfo-data", platforms: [:mingw, :mswin, :x64_mingw, :jruby]
 # Performance-booster for watching directories on Windows
 gem "wdm", "~> 0.1.0" if Gem.win_platform?
 
+
+gem "webrick", "~> 1.7"

Diff for: Gemfile.lock

@@ -3,17 +3,17 @@ GEM
   specs:
     addressable (2.7.0)
       public_suffix (>= 2.0.2, < 5.0)
-    asciidoctor (2.0.10)
+    asciidoctor (2.0.15)
     colorator (1.1.0)
-    concurrent-ruby (1.1.7)
-    em-websocket (0.5.1)
+    concurrent-ruby (1.1.8)
+    em-websocket (0.5.2)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
     eventmachine (1.2.7)
-    ffi (1.13.1)
+    ffi (1.15.0)
     forwardable-extended (2.6.0)
     http_parser.rb (0.6.0)
-    i18n (1.8.5)
+    i18n (1.8.10)
       concurrent-ruby (~> 1.0)
     jekyll (4.1.1)
       addressable (~> 2.4)
@@ -35,22 +35,22 @@ GEM
     jekyll-asciidoc (3.0.0)
       asciidoctor (>= 1.5.0)
       jekyll (>= 3.0.0)
-    jekyll-feed (0.15.0)
+    jekyll-feed (0.15.1)
       jekyll (>= 3.7, < 5.0)
     jekyll-paginate-v2 (3.0.0)
       jekyll (>= 3.0, < 5.0)
     jekyll-sass-converter (2.1.0)
       sassc (> 2.0.1, < 3.0)
-    jekyll-seo-tag (2.6.1)
-      jekyll (>= 3.3, < 5.0)
+    jekyll-seo-tag (2.7.1)
+      jekyll (>= 3.8, < 5.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
     kramdown (2.3.1)
       rexml
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     liquid (4.0.3)
-    listen (3.2.1)
+    listen (3.5.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.4.0)
@@ -60,18 +60,19 @@ GEM
       jekyll-seo-tag (~> 2.1)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
-    public_suffix (4.0.5)
-    rb-fsevent (0.10.4)
+    public_suffix (4.0.6)
+    rb-fsevent (0.11.0)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     rexml (3.2.5)
-    rouge (3.21.0)
+    rouge (3.26.0)
     safe_yaml (1.0.5)
     sassc (2.4.0)
       ffi (~> 1.9)
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
     unicode-display_width (1.7.0)
+    webrick (1.7.0)
 
 PLATFORMS
   ruby
@@ -84,6 +85,7 @@ DEPENDENCIES
   jekyll-paginate-v2
   minima (~> 2.0)
   tzinfo-data
+  webrick (~> 1.7)
 
 BUNDLED WITH
-   2.1.4
+   2.2.16