Refactor runner and fix integration spec

spec/integration/mutant/runner_spec.rb

@@ -1,10 +1,6 @@
 require 'spec_helper'
 
 describe Mutant, 'runner' do
-  before do
-    pending
-  end
-
   around do |example|
     Dir.chdir(TestApp.root) do
       example.run
@@ -14,13 +10,13 @@ describe Mutant, 'runner' do
   it 'allows to run mutant over a project' do
     output = StringIO.new
     runner = Mutant::Runner.run(
-      :pattern => /\ATestApp::/,
       :killer => Mutant::Killer::Rspec,
+      :matcher => Mutant::Matcher::ObjectSpace.new(/\ATestApp::/),
       :reporter => Mutant::Reporter::CLI.new(output)
     )
     runner.fail?.should be(true)
     runner.errors.size.should be(22)
     output.rewind
-    output.lines.grep(/Mutation/).size.should be(22)
+    output.lines.grep(/Mutant alive:/).size.should be(22)
   end
 end