Fix incorrect name for specs with preferred dependency in podfile.lock

lib/cocoapods/installer.rb

@@ -48,7 +48,8 @@ module Pod
       pods.each do |pod|
         unless config.silent?
           marker = config.verbose ? "\n-> ".green : ''
-          puts marker << ( pod.exists? ? "Using #{pod}" : "Installing #{pod}".green )
+          name = pod.top_specification.preferred_dependency ? "#{pod.top_specification.name}/#{pod.top_specification.preferred_dependency} (#{pod.top_specification.version})" : pod.name
+          puts marker << ( pod.exists? ? "Using #{name}" : "Installing #{name}".green )
         end
 
         should_install = !pod.exists?

lib/cocoapods/specification.rb

@@ -406,7 +406,7 @@ module Pod
     end
 
     def to_s
-      preferred_dependency ? "#{name}/#{preferred_dependency} (#{version})" : "#{name} (#{version})"
+      "#{name} (#{version})"
     end
 
     def inspect