Fix issue with IPV6 DNS resolution.
EUCA-2329
first cut at optimizing backing creation on migration dest
[NC] Block attempts to migrate instances when same node is designated as source and destination.

Implements EUCA-5175.
CC migration development

- Change all schedulers to only schedule ENABLED nodes.
- Send a separate destination 'prepare' request for each instance.

Implements EUCA-5069, EUCA-5175.
Add load balancing service endpoint to eucarc - EUCA-5594

A AWS_ELB_URL environment variable is added for load balancing clients.

EUCA-5594
Load balancing SOAP pipeline namespace updated - EUCA-5426

The service namespace is updated to match the one used in the binding.

EUCA-5426
SOAP namespace prefix compatibility change - EUCA-5416

SOAP responses no longer use a prefix for the SOAP envelope namespace
for improved client tool compatibility.

EUCA-5416
Signature V2 request path compatibility change - EUCA-5416

Signature V2 support is updated to allow for clients that incorrectly
canonicalize the request by lower casing the path and skipping the last
"/".

EUCA-5416
PEM private key credential now PKCS#8 format - EUCA-5416

The format of the PEM private key in the downloaded credentials Zip file
is now PKCS#8 format for better tool compatibility. This is referenced
by the EC2_PRIVATE_KEY environment variable.

EUCA-5416
creating a symlink for all VBR items
CC maintenance-mode development.

- [CC] code clean-ups.
- [CC] Extend migraton calls to handle specifying destination-host whitelist/blacklist.
- [CC] Implement migrations specified by instance ID.

Implements EUCA-5069, EUCA-5175.
Auto scaling EBS optimized in create launch configuration - EUCA-5416

Creation of a launch configuration now allows the EBS optimized option
to be specified in SOAP requests.

EUCA-5416
Euare PEM private key now PKCS#8 format - EUCA-5416

The format of the PEM private key output from euare-usercreatecert is
now PKCS#8 format for better tool compatibility.

EUCA-5416
[CC] Implement ROUNDROBIN scheduling for migrations.

Implements EUCA-5175.
EUCA-5658 Fixed "cloudwatch put metric data queue can lose data", simplified
the put metric data queue.
Merge remote-tracking branch 'origin/dev/juphoff/evac' into team/evac
added link-to-... soft links into instance directory, to assist with migration
fixed a problem with link-to-... name on destination; eschewing them for cache
Merge remote-tracking branch 'origin/testing' into dev/juphoff/evac-testing

Conflicts:
	cluster/handlers.c
	cluster/server-marshal.c
	node/handlers.c
EUCA-5662: custom authorization for loadbalancer VM requests
  -- IAM role credentials are used for message authentication purposes
  -- we do not use IAM policy for the authorization because
    1) the internal role should be able to lookup system wide instances and loadbalancers
    2) role delegated from loadbalancer's owner is not how AWS implements
  -- the custom authorization rule checks the source ip of the request, and authorize only when the source ip maps to one of loadbalancer VM