Added Japan! Plus some crash bug fixes, performance improvements and balancing

[1.30]

1. Agreeing to the Freedom Of Information Dilemma now reduces Corruption.
2. Resignation dialog now shows effect on voter perceptions of leader.
3. State Broadcaster now takes a year to implement, and reduces impact of Media Monopoly situation.
4. UK now has the English language correctly affect Immigration demand, not actual Immigration.
5. Some UI improvements to the 'update mod' and 'create mod' screens.
6. Cancelling driverless car laws after the situation triggers will now end that situation.
7. Increased worst case main-screen performance on old integrated intel chips from 30fps to 71fps!
8. Fixed bug where global interest rates showed up as a debt crisis input and would crash if clicked.
9. Japan added!
10. Added earthquake and tsunami events
11. Added back-button to the customise mission screen.
12. Fixed crash when starting a game, then a 2nd game and hitting the electioneering button.
13. Adjusted ministers and donors so they are more likely to be sympathetic to groups your party has made relatively happy. (depending on difficulty settings)
14. Fixed rare crash bug when looking at the financial history of a policy.
15. Accepting a coalition offer now refreshes the report window to remove the offer.
16. Fixed bug where the game could get stuck with an uncloseable window on the electioneering / perceptions screen.
17. Lots of small changes to make maxing out education values harder.
18. Increased impact of unemployment on violent crime, crime and obesity.