* rulesets/ArithmeticScript.h: Remove redundant constructor.
* rulesets/ArithmeticScript.cpp: Provide empty virtual destructor
implementation.
* rulesets/Py_Statistics.cpp: Add debugging output, and remove
rubbish from __init__.
* rulesets/PythonArithmeticScript.cpp: Test implementation of
attribute.
* server/ArithmeticFactory.cpp, server/ArithmeticFactory.h: New
factory class to create instances of scripts to handle
statistics.
* server/EntityFactory.cpp, server/EntityFactory.h: Add new method
and supporting data structures to provide a way to create
statistics objects for newly created Character entities.
* server/PersistantThingFactory.cpp: Add a call to
EntityFactory::addStatisticsScript to the Character
specialisation of PersistantThingFactory::populate, giving
all characters a statistics script now.
* rulesets/mason/world/statistics/Statistics.py: Test implementation
of a class for all character statistics.
* rulesets/ArithmeticScript.h, rulesets/PythonArithmeticScript.h,
rulesets/PythonArithmeticScript.cpp: Stub classes for handling
adding a script to handle Statistics.
