Add test files to minitest-handler cookbook

Added default_test.rb and support/helpers.rb files to the cookbook. This serves two purposes:

1. Give people new to minitest-handler an idea of how their test files should be structured, using code comments as examples.
2. Removes 138 lines of false positive file-missing errors from the Chef-client output when minitest-handler is in the run_list. Examples of these false positives below.

```
[2013-03-05T20:54:22+00:00] ERROR: cookbook_file[tests-minitest-handler-default] (minitest-handler::default line 53) had an error: Cookbook 'minitest-handler' (0.1.2) does not contain a file at any of these locations:
  files/centos-5.8/tests/minitest/default_test.rb
  files/centos/tests/minitest/default_test.rb
  files/default/tests/minitest/default_test.rb; ignore_failure is set, continuing


================================================================================

Error executing action `create` on resource 'cookbook_file[tests-minitest-handler-default]'

================================================================================




Chef::Exceptions::FileNotFound

------------------------------

Cookbook 'minitest-handler' (0.1.2) does not contain a file at any of these locations:
  files/centos-5.8/tests/minitest/default_test.rb
  files/centos/tests/minitest/default_test.rb
  files/default/tests/minitest/default_test.rb




Resource Declaration:

---------------------

# In /tmp/vagrant-chef-1/chef-solo-1/cookbooks/minitest-handler/recipes/default.rb

 53:     cookbook_file "tests-#{cookbook_name}-#{recipe_name}" do
 54:       source "tests/minitest/#{recipe_name}_test.rb"
 55:       cookbook cookbook_name
 56:       path "#{node['minitest']['path']}/#{cookbook_name}/#{recipe_name}_test.rb"
 57:       ignore_failure true
 58:     end
 59:     # copy any helper files from the support directory





Compiled Resource:

------------------

# Declared in /tmp/vagrant-chef-1/chef-solo-1/cookbooks/minitest-handler/recipes/default.rb:53:in `block in from_file'

cookbook_file("tests-minitest-handler-default") do
  provider Chef::Provider::CookbookFile
  action "create"
  ignore_failure true
  retries 0
  retry_delay 2
  path "/var/chef/minitest/minitest-handler/default_test.rb"
  backup 5
  source "tests/minitest/default_test.rb"
  cookbook "minitest-handler"
  cookbook_name :"minitest-handler"
  recipe_name "default"
end





[2013-03-05T20:54:22+00:00] INFO: Processing remote_directory[tests-support-minitest-handler-default] action create (minitest-handler::default line 60)
[2013-03-05T20:54:22+00:00] ERROR: remote_directory[tests-support-minitest-handler-default] (minitest-handler::default line 60) had an error: cookbook minitest-handler has no directory files/default/tests/minitest/support; ignore_failure is set, continuing


================================================================================

Error executing action `create` on resource 'remote_directory[tests-support-minitest-handler-default]'

================================================================================




Chef::Exceptions::FileNotFound

------------------------------

cookbook minitest-handler has no directory files/default/tests/minitest/support




Resource Declaration:

---------------------

# In /tmp/vagrant-chef-1/chef-solo-1/cookbooks/minitest-handler/recipes/default.rb

 60:     remote_directory "tests-support-#{cookbook_name}-#{recipe_name}" do
 61:       source "tests/minitest/support"
 62:       cookbook cookbook_name
 63:       path "#{node['minitest']['path']}/#{cookbook_name}/support"
 64:       recursive true
 65:       ignore_failure true
 66:     end
 67:   end





Compiled Resource:

------------------

# Declared in /tmp/vagrant-chef-1/chef-solo-1/cookbooks/minitest-handler/recipes/default.rb:60:in `block in from_file'

remote_directory("tests-support-minitest-handler-default") do
  provider Chef::Provider::RemoteDirectory
  action :create
  ignore_failure true
  retries 0
  retry_delay 2
  path "/var/chef/minitest/minitest-handler/support"
  recursive true
  source "tests/minitest/support"
  files_backup 5
  files_mode 420
  overwrite true
  cookbook "minitest-handler"
  cookbook_name :"minitest-handler"
  recipe_name "default"
  owner "root"
  group "root"
  mode "0755"
end





[2013-03-05T20:54:22+00:00] INFO: Processing directory[/var/chef/minitest/bluekai-chef-lighttpd] action create (minitest-handler::default line 50)
```