Dead Water Polish translation update

Dead Water Polish translation update, updates delivered by Wesbane.
Heir To The Throne: Polish translation update

Heir To The Throne: Polish translation update, updates delivered by Wesbane.
Eastern Invasion: Polish translation update

Eastern Invasion: Polish translation update, updates delivered by Wesbane.
Legend of Wesmere Polish translation update

Legend of Wesmere: Polish translation update, updates delivered by Rafał.
The Rise of Wesnoth: Polish translation update 

The Rise of Wesnoth: Polish translation update, updates delivered by Rafał.
Removed comments

Removed comments to trigger new build.
Implement define= for mp scenarios and eras

Implemented reloading of configs with define= attributes in both mp_create and mp_wait::join_game().
Added myself to about.cfg and updated changelog.

Conflicts:
	changelog
	src/gamestatus.cpp
	src/gamestatus.hpp
	src/multiplayer_wait.cpp
Add define functionality to modifications.

Added a new method, void create_engine::prepare_for_era_and_mods(),
which sets era and mod in game classification.
Prepare_for_[scenario, campaign] then set their respective defines and reload.

Conflicts:
	changelog
	src/gamestatus.cpp
	src/gamestatus.hpp
Fixed reloading for commandline mp
Implemented defines for largest mainline scenarios
Two Brothers: Polish translation update 

Two Brothers: Polish translation update, updates delivered by Wesbane.
Fixed scoping in multiplayer commandline load

As AI0867 pointed out, config object references were available after they had been made invalid by reloading
don't ignore [advancement] on unit construction.
fixup 'don't ignore [advancement] on unit construction'
fixup includes in ai/manager.?pp
remove unnecessary includes from registry.cpp
fixup includes in actions/undo.cpp
fixup includes in commandline_options
Merge pull request #216 from Rift-Walker/scenario_era_mod_defines_mergable

Add define functionality to scenarios, eras, and mods
Merge pull request #192 from pjackowski/master

Polish translation update