Rakefile: completely remove test and doc tasks

It turns out Echoe creates doc and test tasks that do exactly what
we want.

Rakefile

@@ -1,20 +1,8 @@
 require 'rubygems'
-require 'rake/rdoctask'
 require 'echoe'
 
 task :default => :test
 
-task :test do
-  ENV['SINATRA_ENV'] = 'test'
-end
-
-Rake::RDocTask.new do |rd|
-  rd.main = "README.rdoc"
-  rd.rdoc_files += ["README.rdoc"]
-  rd.rdoc_files += Dir.glob("lib/**/*.rb")
-  rd.rdoc_dir = 'doc'
-end
-
 Echoe.new("sinatra") do |p|
   p.author = "Blake Mizerany"
   p.summary = "Classy web-development dressed in a DSL"