- Added a command-line option to invoke wesnoth's built-in python
interpreter in interactive mode.
- Exposed wesnoth's random number generator to python.
* Improved default the attack selection of default AI
* Improved movement target selection
* Allowed leader to retreat from dangerous location
* Tried to teach AI to understand poison and leadership in attack
selection but result wasn't 100% success
* Fixed some minor bugs found from AI
Improved error and exception handling for formulas. Now we get
detailed info about formula that caused an error, name of file and
number of line in which error occured.