add --delete flag

This makes more sense, and better matches behavior of "real" shared directories behave (say in virtualbox).
Showing how to increase disk size
Update README.md

Specifying security group ID gives the following error without starting any EC2
The security group 'sg-xxxxxxxx' does not exist in default VPC 'vpc-xxxxxxxx' (Fog::Compute::AWS::NotFound)
The EC2 starts after specifying the relevant Security group Name for that ID.
add Configuration block_device_mapping
bugfix: per-region configs didn't work with associate_public_ip
Merge pull request #236 from yuma-iwasaki/update-readme

Update README.md
Merge pull request #231 from droidlabour/patch-1

Update README.md
Merge pull request #237 from timurbatyrshin/per-region-associate_public_ip

bugfix: per-region configs didn't work with associate_public_ip
Merge pull request #201 from hlascelles/Show-disk-size-increase

Show how to increase disk size
Add a proxy command option to SSH commands

Now with more tests! Kinda.

Closes #207
Merge pull request #194 from vasili-zolotov/master

add --delete flag to rsync command
Simple ELB support

Adds functionality of adding and removing instances from AWS ELB.
ELB must exist in the first place.

This partially fixes mitchellh/vagrant-aws#53
Fix formatting of en.yml
Merge pull request #238 from rtyler/elb-rebase

Elb rebase
Issue: Elastic IP association was regularly failing after allocation.

Fix: Elastic IP association now waits 180 seconds after allocation, as per recommendation from AWS support staff (See: https://forums.aws.amazon.com/message.jspa?messageID=471472)