changed README to README.md in gemspec

Signed-off-by: Sebastian Martinez <[email protected]>

Author: Mark Kelly

exception_notification.gemspec

@@ -6,6 +6,6 @@ Gem::Specification.new do |s|
   s.summary = "Exception notification by email for Rails apps"
   s.email = "[email protected]"
 
-  s.files = ['README'] + Dir['lib/**/*']
+  s.files = ['README.md'] + Dir['lib/**/*']
   s.require_path = 'lib'
 end