Merge branch 'save_ext' into jgrpp

# Conflicts:
#	Makefile.src.in
#	findversion.sh
#	projects/determineversion.vbs
#	src/gamelog.cpp
#	src/gamelog_internal.h
#	src/lang/german.txt
#	src/lang/korean.txt
#	src/network/core/config.h
#	src/network/network.cpp
#	src/network/network_udp.cpp
#	src/rev.h
#	src/saveload/afterload.cpp
#	src/saveload/company_sl.cpp
#	src/saveload/depot_sl.cpp
#	src/saveload/gamelog_sl.cpp
#	src/saveload/misc_sl.cpp
#	src/saveload/order_sl.cpp
#	src/saveload/saveload.cpp
#	src/saveload/station_sl.cpp
#	src/saveload/town_sl.cpp
#	src/saveload/vehicle_sl.cpp
#	src/table/settings.ini
#	src/viewport.cpp

src/rev.cpp.in

@@ -53,6 +53,11 @@ const char _openttd_build_date[] = __DATE__ " " __TIME__;
  */
 const char _openttd_build_configure[] = "!!CONFIGURE_INVOCATION!!";
 
+/**
+ * The git revision hash of this version.
+ */
+const char _openttd_revision_hash[] = "!!GITHASH!!";
+
 /**
  * Let us know if current build was modified. This detection
  * works even in the case when revision string is overridden by