Ajout de l'algo de map combinées
Ajout de l'énum pour l'algo combiné
Merge pull request #8 from baaleze/addNewMapGeneratorAlgoritm

Add new map generation algoritm.
Correct bug when choosing a non-default map generator.
Keep previous game parameters when starting a new one with custom
parameters.
remove useless constructor
Add a military power that will be used in wars against other empires.
stub for diplomatic system
Player can select diplomacy state with an other empire.
Permit to discover WAR from city and a weapon.
First draft of diplomatic system.
javadoc
Faster discoverties, ease testing and funnier.
Correct bug in diplo AI.
Ease discovery path to WAR.
Randomize possible discoveries.
Fix bugs when AI delcares wars or sign treaties.
Permit to discover 'treaty' diplomatic state.
Split discoveries into different files. Should also fix eclipse import
issues.
Correct discovery progress algorithm: base time is 10 turns an each
terrain linked to discovery adds 1.