WIP entity rename logic
use a check lookup that covers all checks seen
rake tasks for entity reparent, untested as yet
add in pandik as http check engine
build multiplatform httpchecker
Entity#merge for assimilation of orphaned data
uncomment code
Added AWS SNS Notification Gateway

AWS SNS allows users to send 100 free SMS messages per month, with
pricing being competitive after that.  This gateway allows a user to
define a 'sns' media type, containing a AWS Topic ARN.  Notifications
passed by the notifier with will then get delivered to the specified SNS
topic.
Updated contact spec to allow for SNS notifications
Reverted changes to env.rb

I'm still unable to get _any_ features to run locally (Debian Wheezy,
ruby 1.9.3, redis 2.8 from source) with this line left in. Not sure why,
but evidently it makes the travis builds fail.
Merge branch 'master' into 599_rename_state_with_entity
Add docs for logo image path (Closes: #505)
rework Entity#add to better express actual code paths
distinguish between 'all' and 'enabled' entities
minor cleanup
entities:repatriate rake task
rename a spec
Merge pull request #600 from flapjack/599_rename_state_with_entity

Rename state with entity, and reparent orphaned entity data
Merge pull request #602 from clarkf/master

Added AWS SNS Notification Gateway
Merge pull request #601 from michaelneale/master

httpchecker binary from pandik project