Modernize project codebase (#906)

* Fixed boats falling and a TP glitch #266

* Replaced every C-style cast with C++ ones

* Replaced every C-style cast with C++ ones

* Fixed boats falling and a TP glitch #266

* Updated NULL to nullptr and fixing some type issues

* Modernized and fixed a few bugs

- Replaced most instances of `NULL` with `nullptr`.
- Replaced most `shared_ptr(new ...)` with `make_shared`.
- Removed the `nullptr` macro as it was interfering with the actual nullptr keyword in some instances.

* Fixing more conflicts

* Replace int loops with size_t and start work on overrides

* Add safety checks and fix a issue with vector going OOR

Minecraft.Client/Common/Leaderboards/LeaderboardInterface.cpp

@@ -6,8 +6,8 @@ LeaderboardInterface::LeaderboardInterface(LeaderboardManager *man)
 	m_manager = man;
 	m_pending = false;
 
-	m_filter = (LeaderboardManager::EFilterMode) -1;
-	m_callback = NULL;
+	m_filter = static_cast<LeaderboardManager::EFilterMode>(-1);
+	m_callback = nullptr;
 	m_difficulty = 0;
 	m_type = LeaderboardManager::eStatsType_UNDEFINED;
 	m_startIndex = 0;