Change --projects to not attempt to list installed ones in case of multiple dirs items are cloned to

test/boxen_project_test.rb

@@ -7,13 +7,6 @@ class BoxenProjectTest < Boxen::Test
     assert_equal "foo", project.dir
   end
 
-  def test_installed?
-    project = Boxen::Project.new "foo"
-
-    File.expects(:directory?).with("foo").returns true
-    assert project.installed?
-  end
-
   def test_name
     project = Boxen::Project.new "foo/bar/baz"
     assert_equal "baz", project.name