feat!: add `delimiter`, `capitalize` and `preset` options, rewrite app and lib

[norskeld]

This PR resolves #1.

CLI

• delimiter: Allows to specify any delimiter that will be used to join passphase words. Can be set to an empty string. Defaults to a single space.
• capitalize: Allows to capitalize words. Defaults to false.

• preset: Allows to specify a formatting preset. Formatting presets basically apply a combination of delimiter and capitalize to passphrase words. There are 3 presets:

  • pascal aka PascalCase. Example: ReliablyAgnosticIcinessAttributeBarrelAlarm;
  • kebab aka kebab-case. Example: reliably-agnostic-iciness-attribute-barrel-alarm;
  • snake aka snake_case. Example: reliably_agnostic_iciness_attribute_barrel_alarm.

  Technically, there's also the default one:

  • default. Example: reliably agnostic iciness attribute barrel alarm;

  Note: delimiter and capitalize can't be used with preset.

Library

I rewrote the library so it now exposes, in addition to everything else:

• Passphraser: non-consuming builder that allows to easily configure things up and generate a Passphrase.
• Passphrase: contains generated words, calculated entropy and formatting preset.
• Preset: formatting presets allow to format generated passphrase words using predefined/specified delimiter and capitalize.
• Entropy: contains information about entropy.