Collect the source code adress of memory accesses

[rbertran]

Currently we collect the access patterns (i.e. the target load/store address that generated the exception). We can collect also the origin of the access (i.e. which instruction address generated the exception). This information can be valuable for analysis of patterns and clustering.

In source/trace/system.cpp, in the signal handler, there are a couple of macros to obtain the actual address accessed that generated the fault.