s3: Allow an arbitrary HTTP client to be used
Correct ASG tag types, names, and application

Ref http://docs.aws.amazon.com/AutoScaling/latest/APIReference/API_TagDescription.html.
More complete and correct LC and ASG handling

In particular:

* Add a few fields to structs to better reflect the complete AWS APIs.

* Adjust `member>` handling in XML tags to correctly parse multi-item
  elements (ref #97 for a similar case).
ec2: bump version to 2014-06-15
add option IamInstanceProfile to CreateLaunchConfiguration for allowing aws role base AC
a small code format change
ec2: use later API version
Merge pull request #117 from xuwang/master

Add option IamInstanceProfile to CreateLaunchConfiguration for supporting aws role base AC
ec2: add DeleteTags
Merge pull request #109 from mitchellh/bump-version

ec2: bump version to 2014-06-15
Merge branch 'autoscaling-improvements' of https://github.com/mmcgrana/goamz into mmcgrana-autoscaling-improvements

Conflicts:
	autoscaling/autoscaling.go
Merge branch 'mmcgrana-autoscaling-improvements'
Merge pull request #89 from chouquette/features

s3: Allow an arbitrary HTTP client to be used
s3: HTTPClient
adding security tags
Merge pull request #121 from longnguyen11288/add-sg-tags

adding security tags
ec2: add DescribeAvailabilityZones API support

This commits adds support for the following API endpoint:

http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-DescribeAvailabilityZones.html

This API endpoint is not available. It's available in
launchpad.net/goamz so I copied them here. Tests are working fine
without any problem (I've included them too).
Merge pull request #122 from fatih/master

ec2: add DescribeAvailabilityZones API support
Fixes #123 "Either snapshot ID or volume size must be provided".
Distinguishing between VirtualName, NoDevice, and EBS device mappings.
Merge pull request #124 from thatha/fix_invalid_block_mapping

Fixes #123 "Either snapshot ID or volume size must be provided".