Do not have user/group attributes in json

The attributes are now optional; correct default are set in the
cookbook, but users can change this if wanted.
Fix hardcoded user 'swift'
Use new render_instance_selector helper
Do not expose service user and passwords in UI

End users don't need to change this (and we already generate a random
password); it can still be changed in the json if really needed.
Merge pull request #88 from vuntz/render_instance_selector

https://github.com/crowbar/barclamp-swift/pull/88

Merged by devtool for cloudsleuth
Merge pull request #86 from vuntz/no-user-in-json

https://github.com/crowbar/barclamp-swift/pull/86

Merged by devtool for cloudsleuth
Use :install and not :upgrade for installing packages

As agreed during a community call, we want to use :install to allow
upgrades being controlled instead of automatically installed.
Use new protocol attribute from keystone barclamp
Merge pull request #91 from vuntz/keystone-protocol-attribute

Add non-configurable attribute for http/https use in keystone [4/7]
make key file private
Merge pull request #89 from vuntz/use-install-action

https://github.com/crowbar/barclamp-swift/pull/89

Merged by devtool for cloudsleuth
Merge pull request #92 from SUSE-Cloud/release/pebbles/master

make key file private