Fix exception being thrown for new instance registration with ELB

sysctl: parse bool value as 0/1 and refactor a little bit

ec2_group: rules can't reference containing group fix #5309

Fixing traceback caused by incorrect argument passing to json.dumps

Fixes #5756

Added the ability to add EBS volumes to EC2 instances at creation time

Currently if we are trying to register an instance that has not yet
been registered with the elb an exception is thrown.

Fixing *_plugins configuration names and values

Based on reading of Developing Plugins and the example ansible.cfg file, it seems the sections changed here were created in error by a copy and paste.

This allows a volume to be cloned from a snapshot, a brand new
volume to be created, or an ephemeral volumes to be associated
at time of instance creation.

This avoids any race conditions associated with creating extra volumes
after instance creation (e.g. writes happening before the volume is
mounted).

In addition, this allows the root volume to be edited

Minor documentation fixes.

Fixes 5397

Merge branch 'add_ec2_elb_lb_module' of git://github.com/jsdalton/ansible into jsdalton-add_ec2_elb_lb_module

Add ec2_key module.

key_name is not required when creating ec2 instances

This reverts commit a807e3b9, reversing
changes made to df8ecded.

This reverts commit bedc616f, reversing
changes made to a807e3b9.

This reverts commit e759832d.

Add module support for Rackspace Cloud Files Containers

Module support for Rackspace Cloud Files

rax_dns_record: Add rax_dns_record module

Fix bug where playbook tasks do not escalate privs with 'su'