Reconsider value parsing of std/ini #5614

Currently the parser parses all values into string, but the existing parsers in the ecosystem often work in a different way.

• npm:ini
  • parses true false into booleans
  • no handling for numbers
  • strips double quotes when they are balanced. (no stripping happens if quotes are not balanced)
  • also supports array in the form of array[] = value
• python configparser std module
  • parses all values into string by default
  • optionally you can call getboolean to covert value into boolean (many things are considered boolean such as true/false, yes/no, on/off, 1/0)
  • no quote stripping
• parse_ini_string builtin function in php
  • handles TRUE FALSE as booleans
  • strips quotes around the value. Errors at unbalanced quotes.

(Further investigations of other parsers are welcome)

There seem no consensus in value handling, it might make sense to follow npm:ini when there's differences.