remove quiet assets because rails5 has support it

Gemfile

@@ -44,7 +44,6 @@ gem 'mina-puma', require: false
 gem 'mina-logs', require: false
 
 group :development do
-  gem 'quiet_assets'
   gem 'guard'
   gem 'guard-rails'
   gem 'guard-rspec', require: false

Gemfile.lock

@@ -183,8 +183,6 @@ GEM
       method_source (~> 0.8.1)
       slop (~> 3.4)
     puma (3.4.0)
-    quiet_assets (1.1.0)
-      railties (>= 3.1, < 5.0)
     rack (2.0.0.rc1)
       json
     rack-cors (0.4.0)
@@ -359,7 +357,6 @@ DEPENDENCIES
   nokogiri
   pg
   puma
-  quiet_assets
   rack-cors
   rails (>= 5.0.0.beta3, < 5.1)
   rails-controller-testing
@@ -383,4 +380,4 @@ RUBY VERSION
    ruby 2.2.3p173
 
 BUNDLED WITH
-   1.12.3
+   1.12.5

config/environments/development.rb

@@ -23,6 +23,7 @@ WBlog::Application.configure do
   # This option may cause significant delays in view rendering with a large
   # number of complex assets.
   config.assets.debug = true
+  config.assets.quiet = true
 
   config.middleware.insert_before 0, Rack::Cors do
     allow do