Codechange: rename SettingGuiFlag to SettingFlag (#9332)

It is a lovely organicly grown enum, where it started off with
GUI-only flags, and after that a few flags got added that can be
considered GUI-only (the GUI disables/enables based on them), to
only have flags added that has nothing to do with the GUI.

So be less confusing, and rename them to what they do.

Additionally, I took this opportunity to rename 0ISDISABLED to
reflect what it really does.

src/table/settings/company_settings.ini

@@ -24,7 +24,7 @@ SDT_VAR = static_assert($max <= MAX_$type, "Maximum value for CompanySettings.$v
 
 [defaults]
 flags    = 0
-guiflags = SGF_PER_COMPANY
+guiflags = SF_PER_COMPANY
 interval = 0
 str      = STR_NULL
 strhelp  = STR_CONFIG_SETTING_NO_EXPLANATION_AVAILABLE_HELPTEXT
@@ -50,7 +50,7 @@ cat      = SC_BASIC
 [SDT_VAR]
 var      = engine_renew_months
 type     = SLE_INT16
-guiflags = SGF_PER_COMPANY | SGF_DISPLAY_ABS
+guiflags = SF_PER_COMPANY | SF_GUI_NEGATIVE_IS_SPECIAL
 def      = 6
 min      = -12
 max      = 12
@@ -61,7 +61,7 @@ strval   = STR_CONFIG_SETTING_AUTORENEW_MONTHS_VALUE_BEFORE
 [SDT_VAR]
 var      = engine_renew_money
 type     = SLE_UINT
-guiflags = SGF_PER_COMPANY | SGF_CURRENCY
+guiflags = SF_PER_COMPANY | SF_GUI_CURRENCY
 def      = 100000
 min      = 0
 max      = 2000000
@@ -83,7 +83,7 @@ post_cb  = UpdateServiceInterval
 [SDT_VAR]
 var      = vehicle.servint_trains
 type     = SLE_UINT16
-guiflags = SGF_PER_COMPANY | SGF_0ISDISABLED
+guiflags = SF_PER_COMPANY | SF_GUI_0_IS_SPECIAL
 def      = 150
 min      = 5
 max      = 800
@@ -96,7 +96,7 @@ post_cb  = [](auto new_value) { UpdateServiceInterval(VEH_TRAIN, new_value); }
 [SDT_VAR]
 var      = vehicle.servint_roadveh
 type     = SLE_UINT16
-guiflags = SGF_PER_COMPANY | SGF_0ISDISABLED
+guiflags = SF_PER_COMPANY | SF_GUI_0_IS_SPECIAL
 def      = 150
 min      = 5
 max      = 800
@@ -109,7 +109,7 @@ post_cb  = [](auto new_value) { UpdateServiceInterval(VEH_ROAD, new_value); }
 [SDT_VAR]
 var      = vehicle.servint_ships
 type     = SLE_UINT16
-guiflags = SGF_PER_COMPANY | SGF_0ISDISABLED
+guiflags = SF_PER_COMPANY | SF_GUI_0_IS_SPECIAL
 def      = 360
 min      = 5
 max      = 800
@@ -122,7 +122,7 @@ post_cb  = [](auto new_value) { UpdateServiceInterval(VEH_SHIP, new_value); }
 [SDT_VAR]
 var      = vehicle.servint_aircraft
 type     = SLE_UINT16
-guiflags = SGF_PER_COMPANY | SGF_0ISDISABLED
+guiflags = SF_PER_COMPANY | SF_GUI_0_IS_SPECIAL
 def      = 100
 min      = 5
 max      = 800

src/table/settings/currency_settings.ini

@@ -19,7 +19,7 @@ SDT_VAR = static_assert($max <= MAX_$type, "Maximum value for CurrencySpec.$var
 
 [defaults]
 flags    = SLF_NOT_IN_SAVE | SLF_NO_NETWORK_SYNC
-guiflags = SGF_NONE
+guiflags = SF_NONE
 interval = 0
 str      = STR_NULL
 strhelp  = STR_CONFIG_SETTING_NO_EXPLANATION_AVAILABLE_HELPTEXT

src/table/settings/gameopt_settings.ini

@@ -63,7 +63,7 @@ SDT_VAR = static_assert($max <= MAX_$type, "Maximum value for GameSettings.$var
 
 [defaults]
 flags    = 0
-guiflags = SGF_NONE
+guiflags = SF_NONE
 interval = 0
 str      = STR_NULL
 strhelp  = STR_CONFIG_SETTING_NO_EXPLANATION_AVAILABLE_HELPTEXT

src/table/settings/misc_settings.ini

@@ -37,7 +37,7 @@ SDTG_OMANY = static_assert($max <= MAX_$type, "Maximum value for $var exceeds st
 
 [defaults]
 flags    = SLF_NOT_IN_SAVE | SLF_NO_NETWORK_SYNC
-guiflags = SGF_NONE
+guiflags = SF_NONE
 interval = 0
 str      = STR_NULL
 strhelp  = STR_CONFIG_SETTING_NO_EXPLANATION_AVAILABLE_HELPTEXT

src/table/settings/win32_settings.ini

@@ -25,7 +25,7 @@ SDTG_VAR = static_assert($max <= MAX_$type, "Maximum value for $var exceeds stor
 
 [defaults]
 flags    = SLF_NOT_IN_SAVE | SLF_NO_NETWORK_SYNC
-guiflags = SGF_NONE
+guiflags = SF_NONE
 interval = 0
 str      = STR_NULL
 strhelp  = STR_CONFIG_SETTING_NO_EXPLANATION_AVAILABLE_HELPTEXT

src/table/settings/window_settings.ini

@@ -21,7 +21,7 @@ SDT_VAR = static_assert($max <= MAX_$type, "Maximum value for WindowDesc.$var ex
 
 [defaults]
 flags    = SLF_NOT_IN_SAVE | SLF_NO_NETWORK_SYNC
-guiflags = SGF_NONE
+guiflags = SF_NONE
 interval = 0
 str      = STR_NULL
 strhelp  = STR_CONFIG_SETTING_NO_EXPLANATION_AVAILABLE_HELPTEXT