Changes:

* Removed the "debug.all" option and replaced it with "debug.log".
    * This no longer forces every other debug option to be turned on when set to true.
* Added a debug option to print the stacktrace of the sender when reading throws an exception.
    * Unlike types this must be enabled on both sides for it to work.
    * This is controlled with the option "debug.record_stacktraces"
* Added a simpler cache type (NetObjectCacheSimple)
    * Unlike the full cache, this writes cache data out in-place, rather than requiring a separate network ID.
    * While this makes it simpler to create caches this writes an extra boolean.
* Added markers, which are shown in the debug log if "debug.record_types" is enabled.
