Fix gemspec: rename lib/tasks{migrate => annotate_models_migrate}.rake (#470)

Fix bug introduced by #469.

Author: vergenzt

annotate.gemspec

@@ -14,7 +14,27 @@ Gem::Specification.new do |s|
   s.email = ['alex@stinky.com', 'cuong.tran@gmail.com', 'x@nofxx.com', 'turadg@aleahmad.net', 'jon@cloudability.com']
   s.executables = ['annotate']
   s.extra_rdoc_files = ['README.rdoc', 'CHANGELOG.rdoc', 'TODO.rdoc']
-  s.files = ['AUTHORS.rdoc', 'CHANGELOG.rdoc', 'LICENSE.txt', 'README.rdoc', 'TODO.rdoc', 'annotate.gemspec', 'bin/annotate', 'lib/annotate.rb', 'lib/annotate/active_record_patch.rb', 'lib/annotate/annotate_models.rb', 'lib/annotate/annotate_routes.rb', 'lib/annotate/tasks.rb', 'lib/annotate/version.rb', 'lib/generators/annotate/USAGE', 'lib/generators/annotate/install_generator.rb', 'lib/generators/annotate/templates/auto_annotate_models.rake', 'lib/tasks/annotate_models.rake', 'lib/tasks/annotate_routes.rake', 'lib/tasks/migrate.rake']
+  s.files = [
+    'AUTHORS.rdoc',
+    'CHANGELOG.rdoc',
+    'LICENSE.txt',
+    'README.rdoc',
+    'TODO.rdoc',
+    'annotate.gemspec',
+    'bin/annotate',
+    'lib/annotate.rb',
+    'lib/annotate/active_record_patch.rb',
+    'lib/annotate/annotate_models.rb',
+    'lib/annotate/annotate_routes.rb',
+    'lib/annotate/tasks.rb',
+    'lib/annotate/version.rb',
+    'lib/generators/annotate/USAGE',
+    'lib/generators/annotate/install_generator.rb',
+    'lib/generators/annotate/templates/auto_annotate_models.rake',
+    'lib/tasks/annotate_models.rake',
+    'lib/tasks/annotate_routes.rake',
+    'lib/tasks/annotate_models_migrate.rake'
+  ]
   s.homepage = 'http://github.com/ctran/annotate_models'
   s.licenses = ['Ruby']
   s.require_paths = ['lib']