Add a *ton* of const and constexpr around the codebase. (#1864)

* Add a *ton* of const and constexpr around the codebase.

This makes the codebase compile without strings being cast to non-const char*. I also went through and added constexpr where appropriate for tons of static data.

* Make process definitions const too

Might as well

src/d/actor/d_a_obj_timer.cpp

@@ -131,7 +131,7 @@ namespace {
 
 };  // namespace daObjTimer
 
-actor_process_profile_definition g_profile_Obj_Timer = {
+DUSK_PROFILE actor_process_profile_definition DUSK_CONST g_profile_Obj_Timer = {
     /* Layer ID     */ fpcLy_CURRENT_e,
     /* List ID      */ 10,
     /* List Prio    */ fpcPi_CURRENT_e,