Support multiple outputs disk formats

Using the IMAGE_TYPE env variable, you can select which ouput disk format you want for your image.
Only qcow2 format supports compression.

Change-Id: Ia01d9079c354dbd3cfcf870d86f97ee57bd9d479
Install heat-cfntools from pypi

Then creates symlinks into /opt/aws/bin using the included script.

This replaces the heat-jeos element, so anything that references heat-jeos will need to be replaced with heat-cfntools

Change-Id: Id286b005f69ea364357303b4bbc1ed29d4f0f8f9
Devstack element pulls from master.

Devstack element pulls devstack from trunk
instead of from the tripleo fork.

Change-Id: Ie5b1c325b2464cf1195e8e79857bdea27f9847a2
Merge "Install heat-cfntools from pypi"
Merge "Support multiple outputs disk formats"
Merge "Devstack element pulls from master."