Set `require "object"` as the first one in the prelude so we can use getter, property, etc., macros in the std, plus some other small refactors and simplifictions and fixes.
Made CharReader a struct, refactored and optimized it, together with String#each_char
Fixed String#dump for "#{".
Fixed Call#to_s: missing parens when obj was an array literal or hash with literal with "of"