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.World/Tag.cpp

@@ -27,7 +27,7 @@ Tag::Tag(const wstring &name)
 // 4J - Was Object obj
 bool Tag::equals(Tag *obj)
 {
-	if (obj == NULL )// || !(obj instanceof Tag))
+	if (obj == nullptr )// || !(obj instanceof Tag))
 	{
 		return false;
 	}
@@ -150,7 +150,7 @@ Tag *Tag::newTag(byte type, const wstring &name)
 	case TAG_Compound:
 		return new CompoundTag(name);
 	}
-	return NULL;
+	return nullptr;
 }
 
 const wchar_t *Tag::getTagName(byte type)