Added stack traces and better error reporting in C++

When an error is reported or an assertion fails in C++, a line is now
printed with information about where the error occured, and a stack trace
is printed.

The stacktrace isn't implemented in the HAL because it's not
hardware-dependent, so StackTrace.hpp and StackTrace.cpp are gone.

The Eclipse project template is modified to include "-export-dynamic" in
the linker options, which is necessary for stack traces.

Change-Id: Ie86c14185b13ed603d0fe6467e87ba4f731b1913

hal/lib/Athena/cpp/StackTrace.cpp

@@ -1,9 +0,0 @@
-
-#include "HAL/cpp/StackTrace.hpp"
-
-#include <stdio.h>
-
-
-void printCurrentStackTrace() {
-  // TODO: Implement
-}