Doc: describe what each settings-file is about

src/table/settings/company_settings.ini

@@ -4,6 +4,9 @@
 ; See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 ;
 
+; These are settings that are company-wide. Meaning that if 1 player in a
+; company changes them, it changes for all players.
+
 [pre-amble]
 static void UpdateServiceInterval(int32 new_value);
 static bool CanUpdateServiceInterval(VehicleType type, int32 &new_value);

src/table/settings/currency_settings.ini

@@ -4,6 +4,8 @@
 ; See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 ;
 
+; Settings for the in-game custom currency.
+
 [pre-amble]
 static const SettingTable _currency_settings{
 [post-amble]

src/table/settings/gameopt_settings.ini

@@ -4,6 +4,15 @@
 ; See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 ;
 
+; Settings that used to be saved in the savegame under the OPTS chunk and
+; under "gameopts" in the configuration file, but no longer are. Most of these
+; are now moved to other places.
+;
+; For backwards compatability, this file dictates how both were saved. When
+; a configuration files contains these entries, they are read once, and removed
+; from the configuration file afterwards. Those that are still supported will
+; be saved in their new place.
+
 [pre-amble]
 static const uint GAME_DIFFICULTY_NUM = 18;
 static uint16 _old_diff_custom[GAME_DIFFICULTY_NUM];

src/table/settings/misc_settings.ini

@@ -4,6 +4,9 @@
 ; See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 ;
 
+; Various of settings that are stored in global variables. They are all
+; located under "misc" in the configuration files.
+
 [pre-amble]
 extern std::string _config_language_file;
 

src/table/settings/settings.ini

@@ -4,6 +4,9 @@
 ; See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 ;
 
+; Settings as stored in the main configuration file ("openttd.cfg") and in the
+; savegame PATS chunk (if not flagged not to).
+
 [pre-amble]
 /* Begin - Callback Functions for the various settings */
 static void v_PositionMainToolbar(int32 new_value);

src/table/settings/win32_settings.ini

@@ -4,6 +4,9 @@
 ; See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 ;
 
+; Windows specific settings that are stored in global variables. They are all
+; located under "win32" in the configuration files.
+
 [pre-amble]
 /* win32_v.cpp only settings */
 #if defined(_WIN32) && !defined(DEDICATED)

src/table/settings/window_settings.ini

@@ -4,6 +4,9 @@
 ; See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 ;
 
+; The windows configuration file ("windows.cfg") defines various of properties
+; of all windows.
+
 [pre-amble]
 
 static const SettingTable _window_settings{