Design: Multi-select pattern for Repositories

[catrobson]

As identified in this issue: openshiftio/openshift.io#543

The current control for selecting multiple repositories does not follow general best practices for showing a set of items and allowing the user to multi-select them. Consider other patterns for this behavior.

Acceptance criteria:

• Substitute control identified
• Documented and shared with UXD
• Shared with Launch/Wizard team
• Folded into any work that is already happening for the wizard redesign (Wireframe: Add missions to the wizard #697, Wireframe: New project as progressively building whole screen #740)

[catrobson]

@lwrigh something to consider in your work as well.

[catrobson]

Resolving as part of new wizard design - #816. Closing this issue.