Modernize src/c* src/d* and src/e* files (#6263)

* Modernize src/c* src/d* and src/e* files

* default operator
* redundant init
* delete default constructors on CraftDefinition childs (never used)
* fix some missing init values
* const ref fix reported by clang-tidy
* ranged-based for loops
* simple conditions & returns
* empty stl function instead of size
* emplace_back stl function instead of push_back + construct temp obj
* auto for some iterators
* code style fixes
* c++ stl headers instead of C stl headers (stdio.h -> cstdio)

src/database.cpp

@@ -32,9 +32,9 @@ static inline s16 unsigned_to_signed(u16 i, u16 max_positive)
 {
 	if (i < max_positive) {
 		return i;
-	} else {
-		return i - (max_positive * 2);
 	}
+
+	return i - (max_positive * 2);
 }