Drop VERSION file

Previously the version was in two places: VERSION and safemode.gemspec.
This reads the version from via Rubygems and drops the separate VERSION
file.

cb98c86 already forgot to update the
file and made it go out of sync.

Fixes: cb98c86

Rakefile

@@ -59,7 +59,7 @@ task :default => :test
 
 require 'rdoc/task'
 Rake::RDocTask.new do |rdoc|
-  version = File.exist?('VERSION') ? File.read('VERSION') : ""
+  version = Gem::Specification.find_by_name('safemode').version
 
   rdoc.rdoc_dir = 'rdoc'
   rdoc.title = "safemode #{version}"

safemode.gemspec

@@ -23,7 +23,6 @@ Gem::Specification.new do |s|
     "LICENSE",
     "README.markdown",
     "Rakefile",
-    "VERSION",
     "demo.rb",
     "init.rb",
     "lib/action_view/template_handlers/safe_erb.rb",