Ensure that the diagnostics are user friendly

In the case when the value is a dictionary or array or longer than
the line then the diagnostics output will automatically wrap around
to ensure that the output is user friendly.

Part of the blueprint v3-diagnostics

Change-Id: Ia158fd99aeb0e6296fb232e881d0f01a13407dfc
Closes-bug: #1266402
Merge "Ensure that the diagnostics are user friendly"