Remove ActiveSupport dependency from compact index

.rubocop.yml

@@ -164,6 +164,10 @@ Style/ClassAndModuleChildren:
     - lib/gemcutter/middleware/hostess.rb
     - lib/gemcutter/middleware/redirector.rb
 
+Rails/Present:
+  Exclude:
+    - lib/compact_index/*.rb
+
 Rails/ThreeStateBooleanColumn:
   Enabled: false
 

lib/compact_index/gem_version.rb

@@ -3,7 +3,7 @@
 module CompactIndex
   module GemVersionMethods
     def version_token
-      return "#{number}-#{content_address}" if content_address.present?
+      return "#{number}-#{content_address}" if content_address?
 
       if platform.nil? || platform == "ruby"
         number
@@ -27,12 +27,16 @@ def to_line
       line = "#{version_token} #{deps_line}|checksum:#{checksum}"
       line << ",ruby:#{ruby_version_line}" if ruby_version && ruby_version != ">= 0"
       line << ",rubygems:#{rubygems_version_line}" if rubygems_version && rubygems_version != ">= 0"
-      line << ",platform:= #{platform}" if content_address.present?
+      line << ",platform:= #{platform}" if content_address?
       line
     end
 
     private
 
+    def content_address?
+      !content_address.nil? && !content_address.empty?
+    end
+
     def ruby_version_line
       join_multiple(ruby_version)
     end