Provide new option to support a proposal: with a scale

**Need** A client wants to configure a process so that from a set of proposals, users can evaluate its importance with a 1-10 scale, not just with a simple support action as now. This way, when aggregating all evaluations we have a better understanding of the grade of importance to the community. **Implementation idea** Extend the current support action (votes). You could configure the Supports as Normal (currrent), or Scale, which by default would provide a 1-10 scale. **UX** When configured as Scale, users would be shown something like: ---- "Evaluate the importance of this proposal" [less important --------- more important] 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 ---- **Admin** for each proposal admins would be shown the average evaluation, and maybe the # of votes for each scale step. Also we could provide a way to export the results as CSV for further analysis in external tools. If this is interesting, the extension of support modes ideally would support N modes, so others can implement other ways of evaluating. Although this would make more complex the implementation. Also, ideas about the best way to implement this are more than welcome. Funding available (for a basic implementation)