Fixing problem with gemspec

t-minus.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name = 't-minus'
-  s.version = '0.3.0'
+  s.version = '0.3.1'
   s.description = 'Rails engine and generators that make it easier to create a prelaunch page for your application that can collect email addresses of interested visitors.'
   s.summary = s.description
   s.authors = ['John Grimes']
@@ -11,8 +11,8 @@ Gem::Specification.new do |s|
     'LICENSE',
     'README.markdown'
   ]
-  s.files = `git ls-files -- {app,config,lib,spec}/*`.split("\n")
-  s.test_files = `git ls-files -- {spec}/*`.split("\n")
+  s.files = Dir['{app,config,lib,spec}/**/*']
+  s.test_files = Dir['{spec}/**/*']
   s.required_rubygems_version = Gem::Requirement.new('>= 1.3.6') if s.respond_to? :required_rubygems_version=
 
   s.add_dependency 'createsend', '~> 0.2'