Don't crash when config is nil; Fixes #4

Without this early return, a nil `@resource[:config]` would raise
NoMethodError when friendly_config tried to iterate using `#each`.
fix broken specs
Merge commit 'b557f34c5b638ad1d59ab7b6579e744660ade52c'
Merge commit 'a655f4c488855297a0030684350f2d1a2fa095b5'