bootsnap upgrade

see: https://github.com/Shopify/bootsnap/pull/43#issuecomment-304281474

Gemfile

@@ -3,7 +3,7 @@ source 'https://rubygems.org'
 #source 'http://production.cf.rubygems.org'
 
 # does not install in linux ATM, so hack this for now
-gem 'bootsnap', require: false
+gem 'bootsnap', '0.3.0.pre', require: false
 
 def rails_master?
   ENV["RAILS_MASTER"] == '1'

Gemfile.lock

@@ -62,7 +62,7 @@ GEM
       rack (>= 0.9.0)
     binding_of_caller (0.7.2)
       debug_inspector (>= 0.0.1)
-    bootsnap (0.2.14)
+    bootsnap (0.3.0.pre)
       msgpack (~> 1.0)
     builder (3.2.3)
     bullet (5.4.2)
@@ -400,7 +400,7 @@ DEPENDENCIES
   barber
   better_errors
   binding_of_caller
-  bootsnap
+  bootsnap (= 0.3.0.pre)
   bullet
   byebug
   certified

config/boot.rb

@@ -12,8 +12,6 @@ require 'bundler/setup' if File.exists?(ENV['BUNDLE_GEMFILE'])
 
 
 if ENV['RAILS_ENV'] != 'production'
-  is_mac = !!(RUBY_PLATFORM =~ /darwin/)
-
   require 'bootsnap'
 
   Bootsnap.setup(
@@ -21,7 +19,7 @@ if ENV['RAILS_ENV'] != 'production'
     load_path_cache:      true,        # Should we optimize the LOAD_PATH with a cache?
     autoload_paths_cache: true,        # Should we optimize ActiveSupport autoloads with cache?
     disable_trace:        false,       # Sets `RubyVM::InstructionSequence.compile_option = { trace_instruction: false }`
-    compile_cache_iseq:   is_mac,      # Should compile Ruby code into ISeq cache?
-    compile_cache_yaml:   false        # Should compile YAML into a cache?
+    compile_cache_iseq:   true,        # Should compile Ruby code into ISeq cache?
+    compile_cache_yaml:   false        # Skip YAML cache for now, cause we were seeing issues with it
   )
 end