Update to middleman 4.2.1 for ruby 2.4 fix

Author: kjg

.travis.yml

@@ -9,7 +9,3 @@ rvm:
 
 cache: bundler
 script: bundle exec middleman build
-
-matrix:
-  allow_failures:
-  - rvm: 2.4.0

Gemfile

@@ -1,7 +1,7 @@
 source 'https://rubygems.org'
 
 # Middleman
-gem 'middleman', '~>4.2.0'
+gem 'middleman', '~>4.2.1'
 gem 'middleman-syntax', '~> 3.0.0'
 gem 'middleman-autoprefixer', '~> 2.7.0'
 gem "middleman-sprockets", "~> 4.1.0"

Gemfile.lock

@@ -19,7 +19,7 @@ GEM
       sass (>= 3.2, < 3.5)
     concurrent-ruby (1.0.4)
     contracts (0.13.0)
-    dotenv (2.1.2)
+    dotenv (2.2.0)
     erubis (2.7.0)
     execjs (2.7.0)
     fast_blank (1.0.0)
@@ -30,27 +30,27 @@ GEM
       tilt
     hamster (3.0.0)
       concurrent-ruby (~> 1.0)
-    hashie (3.4.6)
+    hashie (3.5.1)
     i18n (0.7.0)
     kramdown (1.13.2)
     listen (3.0.8)
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
     memoist (0.15.0)
-    middleman (4.2.0)
+    middleman (4.2.1)
       coffee-script (~> 2.2)
       compass-import-once (= 1.0.5)
       haml (>= 4.0.5)
       kramdown (~> 1.2)
-      middleman-cli (= 4.2.0)
-      middleman-core (= 4.2.0)
+      middleman-cli (= 4.2.1)
+      middleman-core (= 4.2.1)
       sass (>= 3.4.0, < 4.0)
     middleman-autoprefixer (2.7.1)
       autoprefixer-rails (>= 6.5.2, < 7.0.0)
       middleman-core (>= 3.3.3)
-    middleman-cli (4.2.0)
+    middleman-cli (4.2.1)
       thor (>= 0.17.0, < 2.0)
-    middleman-core (4.2.0)
+    middleman-core (4.2.1)
       activesupport (>= 4.2, < 5.1)
       addressable (~> 2.3)
       backports (~> 3.6)
@@ -90,7 +90,7 @@ GEM
     public_suffix (2.0.5)
     rack (2.0.1)
     rb-fsevent (0.9.8)
-    rb-inotify (0.9.7)
+    rb-inotify (0.9.8)
       ffi (>= 0.5.0)
     redcarpet (3.4.0)
     rouge (2.0.7)
@@ -101,7 +101,7 @@ GEM
       rack (> 1, < 3)
     thor (0.19.4)
     thread_safe (0.3.5)
-    tilt (2.0.5)
+    tilt (2.0.6)
     tzinfo (1.2.2)
       thread_safe (~> 0.1)
     uglifier (3.0.4)
@@ -111,12 +111,12 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  middleman (~> 4.2.0)
+  middleman (~> 4.2.1)
   middleman-autoprefixer (~> 2.7.0)
   middleman-sprockets (~> 4.1.0)
   middleman-syntax (~> 3.0.0)
   redcarpet (~> 3.4.0)
   rouge (~> 2.0.5)
 
 BUNDLED WITH
-   1.13.6
+   1.14.3