Add warning about download from collectd.org.
Readme Usage Update
Update collectd version to 5.4.0
use collected 5.4.0 from s3.
Version bump.

* collectd default version 5.4.0
* .kitchen.yml update (using s3 collected)
* update Readme file
Merge pull request #20 from applicaster-cookbooks/develop

Alternative collectd downloads.
v0.3.0
Merge branch 'release/0.3.0'