Network: add instance to the debug statement

Allocating and deallocating a network from an instance needs
more info to debug especially when more than one instance
has the same name.

The same change is also made regarding exceptions. That is,
the instance UUID will be used instead of the name.

Change-Id: I624fe77c71f6cb7ca453c863b59f0452c8e6b383
Merge "Network: add instance to the debug statement"