Feature request: better aspect development experience

[gfraiteur]

This is a catch-all ticket to gather ideas related to improving the experience of developing aspects.

Common grievances at this point are:

• It is not easy to know for which targets the aspect succeeds or fails after it has been updated --> Proposal: port the Aspect Explorer from PostSharp and display signs in the code tree when an aspect has errors

• It is annoying to have to close the diff window and open a new one every time there is a change in the aspect. A more "real time" solution is desired, similar to Hot Reload or NCruch.