Make access levels available in section view/edit settings

[#1]

Currently when creating a form, section breaks allow you to specify who can view and who can edit a form. The options are:

View the Project

Edit the Project

Manager the Project

Admin Only

Often you need more granularity than this - e.g. you may want Finance to enter in figures that the project manager can view, but not edit. However, you don't want to give Finance system administrator access.

It would be useful if the view and contribute options could include multi-select access levels as an alternative to the options listed above.