Merge branch 'remove_rubyracer' into 'master'

Remove rubyracer gem

See merge request !1706

Gemfile

@@ -271,7 +271,6 @@ end
 
 group :production do
   gem "gitlab_meta", '7.0'
-  gem "therubyracer"
 end
 
 gem "newrelic_rpm"

Gemfile.lock

@@ -320,7 +320,6 @@ GEM
       addressable (~> 2.3)
     letter_opener (1.1.2)
       launchy (~> 2.2)
-    libv8 (3.16.14.7)
     listen (2.3.1)
       celluloid (>= 0.15.2)
       rb-fsevent (>= 0.9.3)
@@ -479,7 +478,6 @@ GEM
       redis-store (~> 1.1.0)
     redis-store (1.1.4)
       redis (>= 2.2)
-    ref (1.0.5)
     request_store (1.0.5)
     rest-client (1.6.7)
       mime-types (>= 1.16)
@@ -600,9 +598,6 @@ GEM
       tins (~> 0.8)
     terminal-table (1.4.5)
     test_after_commit (0.2.2)
-    therubyracer (0.12.0)
-      libv8 (~> 3.16.14.0)
-      ref
     thin (1.6.1)
       daemons (>= 1.0.9)
       eventmachine (>= 1.0.0)
@@ -789,7 +784,6 @@ DEPENDENCIES
   stamp
   state_machine
   test_after_commit
-  therubyracer
   thin
   tinder (~> 1.9.2)
   turbolinks