Petr Mrázek
1868e0ccf1
Added the `optional-bare` library and refactored NBT reading code to support this change.
optional bare
A simple single-file header-only version of a C++17-like optional for default-constructible, copyable types, for C++98 and later.
Imported from: https://github.com/martinmoene/optional-bare/commit/0bb1d183bcee1e854c4ea196b533252c51f98b81