[Gemfile] Use json 1.7.7 that can compile in ruby 2.2

Gemfile

@@ -11,7 +11,9 @@ source 'https://rubygems.org'
 gemspec
 
 # This is the version that ships with OS X 10.10, so be sure we test against it.
-gem 'json', '1.7.7'
+# At the same time, the 1.7.7 version won't install cleanly on Ruby > 2.2,
+# so we use a fork that makes a trivial change to a macro invocation.
+gem 'json', :git => 'https://github.com/segiddins/json.git', :branch => 'seg-1.7.7-ruby-2.2'
 
 group :development do
   cp_gem 'claide',               'CLAide'

Gemfile.lock

@@ -77,6 +77,13 @@ GIT
   specs:
     cocoapods-try (0.5.1)
 
+GIT
+  remote: https://github.com/segiddins/json.git
+  revision: d4011cabfaa80e9b0da81947b5e9b38dd47359db
+  branch: seg-1.7.7-ruby-2.2
+  specs:
+    json (1.7.7)
+
 PATH
   remote: .
   specs:
@@ -130,7 +137,6 @@ GEM
       sparkr (>= 0.2.0)
       term-ansicolor
       yard (~> 0.8.7.5)
-    json (1.7.7)
     kicker (3.0.0)
       listen (~> 1.3.0)
       notify (~> 0.5.2)
@@ -207,7 +213,7 @@ DEPENDENCIES
   cocoapods-try!
   diffy
   inch
-  json (= 1.7.7)
+  json!
   kicker
   mocha
   mocha-on-bacon