Remove the environment variables in the Gemfile

If you want to set a local path for the gems you can use the local git
repositories feature from the Bundler 1.2.

For example to set the local arel repository:

    bundle config local.arel ~/Work/git/arel

To unset it:

    bundle config --delete local.arel

Bundler will check if the branch of you local repository is the same
that specified in the Gemfile. If you want to disable these branch
checks you can override it by setting this option:

    bundle config disable_local_branch_check true

See more about this feature at http://gembundler.com/v1.2/git.html#local

Gemfile

@@ -2,38 +2,22 @@ source 'https://rubygems.org'
 
 gemspec
 
-if ENV['AREL']
-  gem 'arel', path: ENV['AREL']
-else
-  gem 'arel', github: 'rails/arel'
-end
+gem 'arel', github: 'rails/arel', branch: 'master'
 
 gem 'mocha', '>= 0.11.2', :require => false
-gem 'rack-test', github: "brynary/rack-test"
+gem 'rack-test', github: 'brynary/rack-test'
 gem 'bcrypt-ruby', '~> 3.0.0'
 gem 'jquery-rails'
 
-if ENV['JOURNEY']
-  gem 'journey', path: ENV['JOURNEY']
-else
-  gem 'journey', github: "rails/journey"
-end
+gem 'journey', github: 'rails/journey', branch: 'master'
 
-if ENV['AR_DEPRECATED_FINDERS']
-  gem 'activerecord-deprecated_finders', path: ENV['AR_DEPRECATED_FINDERS']
-else
-  gem 'activerecord-deprecated_finders', github: 'rails/activerecord-deprecated_finders'
-end
+gem 'activerecord-deprecated_finders', github: 'rails/activerecord-deprecated_finders', branch: 'master'
 
 # This needs to be with require false to avoid
 # it being automatically loaded by sprockets
 gem 'uglifier', require: false
 
-if ENV['SPROCKETS_RAILS']
-  gem 'sprockets-rails', path: ENV['SPROCKETS_RAILS']
-else
-  gem 'sprockets-rails', github: 'rails/sprockets-rails'
-end
+gem 'sprockets-rails', github: 'rails/sprockets-rails', branch: 'master'
 
 group :doc do
   # The current sdoc cannot generate GitHub links due
@@ -89,15 +73,11 @@ platforms :jruby do
 end
 
 # gems that are necessary for ActiveRecord tests with Oracle database
-if ENV['ORACLE_ENHANCED_PATH'] || ENV['ORACLE_ENHANCED']
+if ENV['ORACLE_ENHANCED']
   platforms :ruby do
     gem 'ruby-oci8', '>= 2.0.4'
   end
-  if ENV['ORACLE_ENHANCED_PATH']
-    gem 'activerecord-oracle_enhanced-adapter', path: ENV['ORACLE_ENHANCED_PATH']
-  else
-    gem 'activerecord-oracle_enhanced-adapter', github: 'rsim/oracle-enhanced'
-  end
+  gem 'activerecord-oracle_enhanced-adapter', github: 'rsim/oracle-enhanced', branch: 'master'
 end
 
 # A gem necessary for ActiveRecord tests with IBM DB