Set puma's version to 1.6.3

Newest version has problems with logs and newrelic

Gemfile

@@ -12,7 +12,7 @@ gem 'sinatra-contrib', require: nil #github: 'sinatra/sinatra-contrib', require:
 # TODO need to release the gem as soon i'm certain this change makes sense
 gem 'simple_states',      github: 'svenfuchs/simple_states', branch: 'sf-set-state-early'
 
-gem 'puma'
+gem 'puma', '1.6.3'
 gem "sentry-raven",    github: 'getsentry/raven-ruby'
 gem 'yard-sinatra',    github: 'rkh/yard-sinatra'
 gem 'rack-contrib',    github: 'rack/rack-contrib'

Gemfile.lock

@@ -205,8 +205,8 @@ GEM
       coderay (~> 1.0.5)
       method_source (~> 0.8)
       slop (~> 3.4)
-    puma (2.0.1)
-      rack (>= 1.1, < 2.0)
+    puma (1.6.3)
+      rack (~> 1.2)
     pusher (0.11.3)
       multi_json (~> 1.0)
       signature (~> 0.1.6)
@@ -303,7 +303,7 @@ DEPENDENCIES
   micro_migrations!
   mocha (~> 0.12)
   pry
-  puma
+  puma (= 1.6.3)
   rack-cache (~> 1.2)
   rack-contrib!
   rake (~> 0.9.2)