Yorm

- Replaced all utility functions with ORM-like tools.
- Removed the ability to check for existing files in `sync()`.
- Renamed and consolidated custom exceptions.
- Renamed sync parameter `auto=True` to `auto_save=True`.
- Renamed sync parameter `strict=True` to `auto_track=False`.
- Added sync parameter `auto_create` to defer file creation to ORM functions.

- Now preserving order of `attr` decorators on `Dictionary` converters.

- Updated `String` to fetch `true` and `false` as strings.

- Now preserving order of `attr` decorators.
- Now limiting `attr` decorator to a single argument.
- Added `List.of_type()` factory to create lists with less boilerplate.

- Fixed handling of `None` in `NullableString`.

- Added preliminary support for JSON serialization. (credit: pr0xmeh)
- Renamed `yorm.converters` to `yorm.types`.
- Now maintaining the signature on mapped objects.
- Disabled attribute inference unless `strict=False`.
- Fixed formatting of `String` to only use quotes if absolutely necessary.