make swift always available but optional
always initialize _machines, helps when debugging with fake data
rename core to required, and support units bouncing between required and nonrequired (e.g. swift & swift-proxy)
Add ability to filter machines list by the charms that are placed on the machines
Merge pull request #273 from Ubuntu-Solutions-Engineering/optional-swift

Make swift always available but optional
add large test file for FAKE_API_DATA
add hidden env var to specify a node for juju bootstrap
Merge pull request #274 from Ubuntu-Solutions-Engineering/filter-by-assignment

Add ability to filter machines list by placement
Merge pull request #276 from Ubuntu-Solutions-Engineering/force-bootstrap-to

add hidden env var to specify a node for juju bootstrap
Refine installer info messages and dialog boxes

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
add support for descriptions in radio input

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
use correct dict

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
use first item in tuple for install tpye

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
more text updates to fix ellipsis

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
Fix cli text for uninstall

Ref: #254

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
Fix single doc guide for uninstalling OpenStack

Ref: #254

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
Fix info message in neutron post_proc

Ref: #254

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
tweak button positioning and colors as per design feedback
fix access to removed btn_columns, make dialog height high enough for buttons
further styling for machine wait screen, and make tab work there too