add gemfile.lock to gitignore

.gitignore

@@ -1 +1,2 @@
 _site/
+Gemfile.lock

Gemfile.lock

@@ -1,64 +0,0 @@
-GEM
-  remote: https://rubygems.org/
-  specs:
-    addressable (2.5.2)
-      public_suffix (>= 2.0.2, < 4.0)
-    colorator (1.1.0)
-    concurrent-ruby (1.0.5)
-    em-websocket (0.5.1)
-      eventmachine (>= 0.12.9)
-      http_parser.rb (~> 0.6.0)
-    eventmachine (1.2.7)
-    ffi (1.9.25)
-    forwardable-extended (2.6.0)
-    http_parser.rb (0.6.0)
-    i18n (0.9.5)
-      concurrent-ruby (~> 1.0)
-    jekyll (3.8.4)
-      addressable (~> 2.4)
-      colorator (~> 1.0)
-      em-websocket (~> 0.5)
-      i18n (~> 0.7)
-      jekyll-sass-converter (~> 1.0)
-      jekyll-watch (~> 2.0)
-      kramdown (~> 1.14)
-      liquid (~> 4.0)
-      mercenary (~> 0.3.3)
-      pathutil (~> 0.9)
-      rouge (>= 1.7, < 4)
-      safe_yaml (~> 1.0)
-    jekyll-sass-converter (1.5.2)
-      sass (~> 3.4)
-    jekyll-watch (2.1.2)
-      listen (~> 3.0)
-    kramdown (1.17.0)
-    liquid (4.0.1)
-    listen (3.1.5)
-      rb-fsevent (~> 0.9, >= 0.9.4)
-      rb-inotify (~> 0.9, >= 0.9.7)
-      ruby_dep (~> 1.2)
-    mercenary (0.3.6)
-    pathutil (0.16.1)
-      forwardable-extended (~> 2.6)
-    public_suffix (3.0.3)
-    rb-fsevent (0.10.3)
-    rb-inotify (0.9.10)
-      ffi (>= 0.5.0, < 2)
-    rouge (3.3.0)
-    ruby_dep (1.5.0)
-    safe_yaml (1.0.4)
-    sass (3.6.0)
-      sass-listen (~> 4.0.0)
-    sass-listen (4.0.0)
-      rb-fsevent (~> 0.9, >= 0.9.4)
-      rb-inotify (~> 0.9, >= 0.9.7)
-
-PLATFORMS
-  ruby
-
-DEPENDENCIES
-  jekyll (~> 3.8.4)
-  tzinfo-data
-
-BUNDLED WITH
-   1.16.6