synchronize: allow ansible_ssh_host to be templated

This is already enabled in the runner also.
Allow multiple users to use ec2 inventory scripts

Move the ec2 cache files from a shared /tmp location to the
user's ansible tmp directory.
Fixed false positive on initctl as enable_cmd

Also on update-rc.d
In service module
initial commit of a basic rolling upgrade guide, based on the lamp_haproxy example
flesh out the CI/CD and load balancer sections a bit
tweak some links and phrasing
Fail EC2 inventory better with restricted EC2 users

If a user has full EC2 access but no RDS access, the user
should still be able to query the EC2 inventory, although
will not obtain any information about any RDS instances.
Added prev_state for directory
Move more responsibility to common EC2 module

Moved `AWS_REGIONS` into `ec2` module
Created `ec2_connect` method in `ec2` module
Updated modules able to use `ec2_connect` and `AWS_REGIONS`
Add guide_rax.rst
Merge branch 'rax-guide' of git://github.com/sivel/ansible into devel
Wrap lines a bit tighter for easier editing.
Some minor tweaks to make things a little more tutorial-like, moved credentials section up higher, etc.
Merge branch 'lamp_tutorial' of git://github.com/tgerla/ansible into devel
Some slight tweaks to the continuous delivery docs.
Various syntax and layout things, add Galaxy to docs
Remove quotes aroung etcd_url value

I get errors like this with etcd_url = 'http://127.0.0.1:4001':
urllib2.URLError: <urlopen error unknown url type: 'http>
Make sure action plugin copy cleans up tmp dir

The copy action plugin creates its own tmp dir for each file that it
copies to the target machine.  However, it does not clean up the
original tmp path it was given when run() is called.  This cleans up the
tmp path before it begins looping on source files.
Merge pull request #5384 from sfromm/cleantmpdir

Make sure action plugin copy cleans up tmp dir
minor typo fixes for the rolling update guide