Support for whyrun on user_account provider about chef-user

[ranjib]

should be available on 0.4 release onwards.

[patcon]

I'm getting an error with whyrun too in 0.4.2:

* user_account[patcon] action create
* directory[/home/patcon parent directory] action create (up to date)
* user[patcon] action create
- Would create user patcon

================================================================================
Error executing action `create` on resource 'user_account[patcon]'
================================================================================

ArgumentError
-------------
can't find user for patcon

Cookbook Trace:
---------------
/var/chef/cache/cookbooks/user/providers/account.rb:134:in `getpwnam'
/var/chef/cache/cookbooks/user/providers/account.rb:134:in `block in home_dir_resource'
/var/chef/cache

[patcon]

This is resolved by an unreleased commit:
7d445ed