Update gemspec.

scrivener.gemspec

@@ -1,21 +1,16 @@
 require "./lib/scrivener"
 
 Gem::Specification.new do |s|
-  s.name              = "scrivener"
-  s.version           = Scrivener::VERSION
-  s.summary           = "Validation frontend for models."
-  s.description       = "Scrivener removes the validation responsibility from models and acts as a filter for whitelisted attributes."
-  s.authors           = ["Michel Martens"]
-  s.email             = ["michel@soveran.com"]
-  s.homepage          = "http://github.com/soveran/scrivener"
-  s.files = Dir[
-    "LICENSE",
-    "AUTHORS",
-    "README.md",
-    "Rakefile",
-    "lib/**/*.rb",
-    "*.gemspec",
-    "test/**/*.rb"
-  ]
+  s.name         = "scrivener"
+  s.version      = Scrivener::VERSION
+  s.summary      = "Validation frontend for models."
+  s.description  = "Scrivener removes the validation responsibility from models and acts as a filter for whitelisted attributes."
+  s.authors      = ["Michel Martens"]
+  s.email        = ["michel@soveran.com"]
+  s.homepage     = "http://github.com/soveran/scrivener"
+  s.license      = "MIT"
+
+  s.files = `git ls-files`.split("\n")
+
   s.add_development_dependency "cutest"
 end