Bump websocket-extensions from 0.1.3 to 0.1.5

Bumps [websocket-extensions](https://github.com/faye/websocket-extensions-ruby) from 0.1.3 to 0.1.5.
- [Release notes](https://github.com/faye/websocket-extensions-ruby/releases)
- [Changelog](https://github.com/faye/websocket-extensions-ruby/blob/master/CHANGELOG.md)
- [Commits](faye/websocket-extensions-ruby@0.1.3...0.1.5)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -73,6 +73,7 @@ GEM
       rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
       thor (>= 0.14, < 2.0)
+    libv8 (3.16.14.19)
     listen (3.0.8)
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
@@ -89,6 +90,7 @@ GEM
     nio4r (2.3.1)
     nokogiri (1.8.2)
       mini_portile2 (~> 2.3.0)
+    pg (1.2.3)
     popper_js (1.12.9)
     puma (3.11.4)
     rack (2.0.5)
@@ -121,6 +123,7 @@ GEM
     rb-fsevent (0.10.3)
     rb-inotify (0.9.10)
       ffi (>= 0.5.0, < 2)
+    ref (2.0.0)
     sass (3.5.6)
       sass-listen (~> 4.0.0)
     sass-listen (4.0.0)
@@ -145,6 +148,9 @@ GEM
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
     sqlite3 (1.3.13)
+    therubyracer (0.12.3)
+      libv8 (~> 3.16.14.15)
+      ref
     thor (0.20.0)
     thread_safe (0.3.6)
     tilt (2.0.8)
@@ -162,7 +168,7 @@ GEM
       railties (>= 5.0)
     websocket-driver (0.6.5)
       websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.3)
+    websocket-extensions (0.1.5)
 
 PLATFORMS
   ruby
@@ -175,12 +181,14 @@ DEPENDENCIES
   jbuilder (~> 2.5)
   jquery-rails
   listen (~> 3.0.5)
+  pg
   puma (~> 3.0)
-  rails (~> 5.0.0, >= 5.0.0.1)
+  rails (~> 5.0.0)
   sass-rails (~> 5.0)
   spring
   spring-watcher-listen (~> 2.0.0)
   sqlite3
+  therubyracer
   turbolinks (~> 5)
   tzinfo-data
   uglifier (>= 1.3.0)