Spring AOP's MethodInvocationProceedingJoinPoint throws exceptions in the
returned SourceLocation instead of just returning null.
- added minimum report depth to reporter
- log a corrupt call tree
logic error: last entry was never updated, so tree would be corrupt
quite quickly.
Reworked the stacktrace recorder and added a basic recorder which can be
passed around through the code (or put in a singleton).
updated documentation