Feature: implemented string.format

[reloginn]

Features

• Fully supports all specifiers described in Lua 5.4 manual.
• Compared to the previous PR, %p has been implemented and support has been added for types that can be converted to String using __tostring.

Note

The implementation was based on the sprintf, but according to the Lua 5.4 manual:

The format string follows the same rules as the ISO C function sprintf. The only differences are that the conversion specifiers ?> and modifiers F, n, *, h, L, and l are not supported and that there is an extra specifier, q.

so I just removed the unsupported specifiers and added q.