The basic Exception can be used anywhere in the code but however, no
program nor library should ever raise Exception directly: it's not
specific enough to be helpful. This fix better handles the exceptions by
removing the Exception occurencies and adding a new SynergyError type.
Bug: #1690795
Change-Id: I202e063198ee9aef7397bad9b8398c24d52b5fe1
Sem-Ver: bugfix