Ensure that all actions are compared to fixed point in time (ie. world update start) (#18910)

- Actions will not be dependent on processing moment
- Increased GameObjects cooldown resolution to milliseconds, fixes arming time of traps to be exactly one second and not something from range (1000, 1999)
- Created GameTime namespace and UpdateTime class and moved there some code out of world

(cherrypicked from 7567cafec8)

src/server/game/Time/GameTime.cpp

@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2008-2017 TrinityCore <http://www.trinitycore.org/>
+
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "GameTime.h"
+#include "Timer.h"
+
+namespace GameTime
+{
+    time_t const StartTime = time(nullptr);
+
+    time_t GameTime = 0;
+    uint32 GameMSTime = 0;
+
+    std::chrono::system_clock::time_point GameTimeSystemPoint = std::chrono::system_clock::time_point::min();
+    std::chrono::steady_clock::time_point GameTimeSteadyPoint = std::chrono::steady_clock::time_point::min();
+
+    time_t GetStartTime()
+    {
+        return StartTime;
+    }
+
+    time_t GetGameTime()
+    {
+        return GameTime;
+    }
+
+    uint32 GetGameTimeMS()
+    {
+        return GameMSTime;
+    }
+
+    std::chrono::system_clock::time_point GetGameTimeSystemPoint()
+    {
+        return GameTimeSystemPoint;
+    }
+
+    std::chrono::steady_clock::time_point GetGameTimeSteadyPoint()
+    {
+        return GameTimeSteadyPoint;
+    }
+
+    uint32 GetUptime()
+    {
+        return uint32(GameTime - StartTime);
+    }
+
+    void UpdateGameTimers()
+    {
+        GameTime = time(nullptr);
+        GameMSTime = getMSTime();
+        GameTimeSystemPoint = std::chrono::system_clock::now();
+        GameTimeSteadyPoint = std::chrono::steady_clock::now();
+    }
+}