provision IAM credentials for S3 access
update knife config to enable cloudformation IAM capability
[cloudformation] move chef user data into a registry item
[cloudformation] update chef metadata registry to retrieve encrypted data bag secret from s3
[cloudformation] whitespace
[cloudformation] change base bucket name to match existing bucket naming style
[cloudformation] add instance iam metadata to registry
[cloudformation] update launch_configuration dynamic to use iam metadata from registry
[cloudformation] add wait handle and wait condition to ec2 instance dynamic
[cloudformation] add elb dynamic
[cloudformation] add nexus template
[cloudformation] remove spurious underscore in launch configuration security group name
add some librarian paths to gitignore

(cherry picked from commit b965435a1d0b50432e95d68b19da85f218dd8059)
ignore .kitchen

(cherry picked from commit 42e7d467e6827ad2b323df38d2864b354a000b6b)
remove metadata.json files
loosen papertrail-rsyslog dependency on rsyslog so librarian can resolve
add signifyd_nexus cookbook and dependencies
update signifyd_nexus cookbook
ignore .rb data bag items

this allows us to locally store the cleartext of data bag items as
ruby hashes and only commit the encrypted json generated using
encrypt_data_bag gem
add encrypt_data_bag gem to bundle