Flow system for UI components

[jvalkeal]

Work done for #360 can obviously used manually by creating all these components manually and then hooking up a "flow" to combine all logic together. There is a quite a bit of code to write to:

• Construct a component
• Handle logic to run it component
• Pass possible context stuff from one component to next one, etc

Would be beneficial to have all this as a "wizard" flow so that user could just concentrate on creating flows to get an end result. What comes for an actual "wizard" depend on what happens with each components. Simplest thing is to have set of components as a hard coded list as a static list, other more sophisticate list of flow is to make decisions on a tree structure or other semi non deterministic structure to end up through a graph of components into final result.