Update rubocop-rspec to version 2.4.0

Gemfile.lock

@@ -253,7 +253,6 @@ GEM
       ruby-vips (>= 2.0.17, < 3)
     io-like (0.3.1)
     iso-639 (0.2.8)
-    jaro_winkler (1.5.4)
     jquery-datatables-rails (3.4.0)
       actionpack (>= 3.1)
       jquery-rails
@@ -360,9 +359,9 @@ GEM
     paper_trail (10.3.1)
       activerecord (>= 4.2)
       request_store (~> 1.1)
-    parallel (1.18.0)
-    parser (2.6.5.0)
-      ast (~> 2.4.0)
+    parallel (1.20.1)
+    parser (3.0.2.0)
+      ast (~> 2.4.1)
     pdf-core (0.9.0)
     pdf-inspector (1.3.0)
       pdf-reader (>= 1.0, < 3.0.a)
@@ -503,18 +502,27 @@ GEM
       rspec-mocks (~> 3.6.0)
       rspec-support (~> 3.6.0)
     rspec-support (3.6.0)
-    rubocop (0.75.1)
-      jaro_winkler (~> 1.5.1)
+    rubocop (1.19.0)
       parallel (~> 1.10)
-      parser (>= 2.6)
+      parser (>= 3.0.0.0)
       rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 1.8, < 3.0)
+      rexml
+      rubocop-ast (>= 1.9.1, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 1.4.0, < 1.7)
-    rubocop-rspec (1.36.0)
-      rubocop (>= 0.68.1)
+      unicode-display_width (>= 1.4.0, < 3.0)
+    rubocop-ast (1.10.0)
+      parser (>= 3.0.1.1)
+    rubocop-rails (2.11.3)
+      activesupport (>= 4.2.0)
+      rack (>= 1.1)
+      rubocop (>= 1.7.0, < 2.0)
+    rubocop-rspec (2.4.0)
+      rubocop (~> 1.0)
+      rubocop-ast (>= 1.1.0)
     ruby-oembed (0.12.0)
     ruby-openid (2.9.2)
-    ruby-progressbar (1.10.1)
+    ruby-progressbar (1.11.0)
     ruby-rc4 (0.1.5)
     ruby-vips (2.1.2)
       ffi (~> 1.12)
@@ -602,7 +610,7 @@ GEM
     unf (0.1.4)
       unf_ext
     unf_ext (0.0.7.7)
-    unicode-display_width (1.6.1)
+    unicode-display_width (2.0.0)
     unicode_utils (1.4.0)
     unobtrusive_flash (3.3.1)
       railties
@@ -722,6 +730,7 @@ DEPENDENCIES
   rspec-activemodel-mocks
   rspec-rails
   rubocop
+  rubocop-rails
   rubocop-rspec
   ruby-oembed
   sass-rails (>= 4.0.2)