Update the master spec repo after running `pod setup' and the repo already exists. Closes #67.

lib/cocoapods/command/setup.rb

@@ -11,8 +11,7 @@ module Pod
 
           https://github.com/CocoaPods/Specs
 
-      If the clone already exists, it will ensure that it points to the correct
-      remote.}
+      If the clone already exists, it will ensure that it is up-to-date.}
       end
 
       def initialize(argv)
@@ -28,12 +27,17 @@ module Pod
       end
 
       def update_master_repo_remote_command
-        @command ||= Repo.new(ARGV.new(['set-url', 'master', master_repo_url]))
+        Repo.new(ARGV.new(['set-url', 'master', master_repo_url]))
+      end
+
+      def update_master_repo_command
+        Repo.new(ARGV.new(['update', 'master']))
       end
 
       def run
         if (config.repos_dir + 'master').exist?
           update_master_repo_remote_command.run
+          update_master_repo_command.run
         else
           add_master_repo_command.run
         end

spec/functional/command_spec.rb

@@ -11,16 +11,6 @@ describe "Pod::Command" do
     git_config('master', 'remote.origin.url').should == fixture('spec-repos/master').to_s
   end
 
-  it "updates an existing `master' clone to point to the correct remote (migration for version 0.2.0 -> 0.3.0)" do
-    dir = temporary_directory + 'cocoapods'
-    dir.mkpath
-    FileUtils.cp_r(fixture('spec-repos/master').to_s, dir.to_s)
-    command = Pod::Command.parse('setup', '--silent')
-    def command.master_repo_url; 'git://some-other-remote'; end
-    command.run
-    git_config('master', 'remote.origin.url').should == 'git://some-other-remote'
-  end
-
   it "adds a spec-repo" do
     add_repo('private', fixture('spec-repos/master'))
     git_config('private', 'remote.origin.url').should == fixture('spec-repos/master').to_s