Merge pull request #175 from dalerank/master

Compilers, Aqueducts, EmpireMap, GUI
Merge pull request #177 from dalerank/master

Empire map fix
Merge pull request #180 from dalerank/master

WaterOverlay improved. TradeAdviser improved.
Fix missing include.
Merge pull request #181 from ImperatorPrime/master

Fix missing include.
Add safety picture using in some classes.
Merge pull request #185 from dalerank/master

Get changes from dalerank
FileDir::getApplicationDir() implementation for OSX
Merge pull request #186 from veprbl/osx-patch

FileDir::getApplicationDir() implementation for OSX
Merge branch 'master' of https://github.com/gecube/opencaesar3
GameDate in own class now.