Adding CIDR support to SG

Allows adding CIDR destinations/sources to security groups, instead of
the per-app handling before

Adds extra logging and checks to make sure you don't try to define a
security group with a CIDR mask
Merge pull request #3 from vjanelle/cloudcaster-cidr-sg

from @vjanelle Adding CIDR support to SG
Fix accidentally creating a tuple

< vjanelle>  549                     print type(str(allowsg.id))
< vjanelle>  550 kwargs['src_security_group_group_id'] = str(allowsg.id),
< vjanelle>  551                     print type(kwargs['src_security_group_group_id'])
< vjanelle> <type 'str'>
< vjanelle> <type 'tuple'>
< AeroNotix> 550 str(..),
< AeroNotix> notice the trailing comma
< AeroNotix> that makes it a tuple
< vjanelle> oh
< AeroNotix> Done *that* before
< AeroNotix> lolz
< okeuday1> yeah, that is annoying
< vjanelle> AeroNotix: thanks
< vjanelle> AeroNotix: I do not know how long that would've taken me to figure out
< AeroNotix> vjanelle: such an innocuous little thing.
< AeroNotix> vjanelle: it should be a syntax error imho
Merge pull request #4 from vjanelle/cloudcaster-cidr-sg

Fix accidentally creating a tuple
app:elb becomes optional, and errors when elb is missing.  remove requirement for default elb registration
doc removal of default elb, and optional elb usage
remove verbose printing of ami mapping.  trap missing ami mapping if it will affect creation of new launchconfig or instances
Merge pull request #5 from WrathOfChris/cm-cloudcaster-elb-optional

ELB Optional