Add localization "foundation" (many code changes)

This commit adds most of the code changes necessary for making the game
translatable, but does not yet "unhardcode" nearly all of the strings
(except in a few cases where it was hard to separate added
loc::gettexts from foundational code changes, or all the localization-
related menus which were also added by this commit.)

This commit is part of rewritten history of the localization branch.
The original (unsquashed) commit history can be found here:
https://github.com/Dav999-v/VVVVVV/tree/localization-orig

desktop_version/src/Game.h

@@ -60,6 +60,14 @@ namespace Menu
         audiooptions,
         accessibility,
         controller,
+        language,
+        translator_main,
+        translator_options,
+        translator_options_limitscheck,
+        translator_options_stats,
+        translator_maintenance,
+        translator_maintenance_sync,
+        translator_error_setlangwritedir,
         cleardatamenu,
         clearcustomdatamenu,
         setinvincibility,
@@ -290,6 +298,7 @@ public:
     //Main Menu Variables
     std::vector<MenuOption> menuoptions;
     int currentmenuoption ;
+    bool menutestmode;
     enum Menu::MenuName currentmenuname;
     enum Menu::MenuName kludge_ingametemp;
     enum SLIDERMODE slidermode;
@@ -330,6 +339,7 @@ public:
     bool noflashingmode;
     int slowdown;
     int get_timestep(void);
+    bool physics_frozen(void);
 
     bool nodeathmode;
     int gameoverdelay;
@@ -343,6 +353,7 @@ public:
     bool intimetrial, timetrialparlost;
     int timetrialcountdown, timetrialshinytarget, timetriallevel;
     int timetrialpar, timetrialresulttime, timetrialresultframes, timetrialrank;
+    bool timetrialcheater;
     int timetrialresultshinytarget, timetrialresulttrinkets, timetrialresultpar;
     int timetrialresultdeaths;
 
@@ -423,7 +434,7 @@ public:
 
     //Some stats:
     int totalflips;
-    std::string hardestroom;
+    std::string hardestroom; // don't change to C string unless you wanna handle language switches (or make it store coords)
     int hardestroomdeaths, currentroomdeaths;
 
 
@@ -483,6 +494,9 @@ public:
     bool incompetitive(void);
 
     bool nocompetitive(void);
+    bool nocompetitive_unless_translator(void);
+
+    void sabotage_time_trial(void);
 
     bool over30mode;
     bool showingametimer;