Updated Opsworks to take advantage of VPC.
The name parameter is optional for the CopyImage API call of ec2.

Make the name parameter optional for the copy_image method. The default value is the same as that
of the source AMI being copied [1].

[1]: http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-CopyImage.html
Updated Opsworks docstrings to latest.
Updated Elasticache to support Redis & replication.
s3put: accept headers values containing "="

s3put tries to split headers on the "=" sign. Some headers include a "=" sign (e.g. max-age), and can't be used. 

This pull request splits on the first equal sign to support those.

Caveat: if a user uses the command correctly (`s3put --header "header1=value1 header2=value2"), they won't get an exception.
Added docs about the included CLI tools & recommended people check out the AWS-CLI.
Merge branch 'elasticache-redis' into develop
Added notes for the release.
Bumping version to 2.12.0
Merge branch 'release-2.12.0' into develop

* release-2.12.0:
  Bumping version to 2.12.0
Added dev release notes back in, as well as a template for future laziness.
Fixed the creation of EC2 VPC instances with public IPs.
Added Opsworks to the docs & cleaned up a bunch of Sphinx build errors.
Altered SDB to no longer cause errors when building the docs.
Merge branch 'opsworks-vpc' into develop
Updated release notes to mention the Opsworks VPC support.
SNS ``publish`` now uses POST.
Merge branch 'ec2-public-ip-fix' into develop
Merge branch 'docs-cleanup' into develop
Added release notes for the recent merges.