Fix MessageEngine always being initialized as English

Closes #314

loadSettings() needs to be run after the ModManager is created, but *before*
MessageEngine is created.
README.engine: move installation related text into seperate INSTALL.engine file.
Update of swedish translation.
Merge pull request #313 from stefanbeller/master

Introduce a setting 'audio' in the config file to disable audio. 
Merge pull request #315 from dorkster/bugfixes

Fix MessageEngine always being initialized as English
Merge pull request #317 from hean01/translation

Update of swedish translation.
Merge pull request #316 from matthiaskrgr/master

    README: move installation related text into seperate INSTALL file.
Fix issue #318 combat text wrong location
Avoid div by 0 on random currency loot
Fixes compiler warnings about shadowing global declaration
of screen.
Merge pull request #320 from hean01/bugfixes

Fixes compiler warnings about shadowing global declaration of screen.
Removed duplicated code logic and free allocated WidgetLabel object.
Fixes #319.
Merge remote-tracking branch 'upstream/master' into bugfixes

Conflicts:
	src/CombatText.cpp
Allow the keyword "currency" in enemy loot entries
Merge branch 'master' of https://github.com/clintbellanger/flare-engine
Merge pull request #321 from hean01/bugfixes

Removed duplicated code logic and free allocated WidgetLabel object.
CMakeLists.txt: remove -pg on default.