Removed optional find by identifier conditions.
Removed #find_with_token? and #toggle_identifier method support.

- These were used as a global setting to toggle between token and
  primary key.
- Was used to dictate .find_by_identifier and #to_param behavior but
  can be limited on only the .find_by_identifier method now.
Refactored .find_by_identifier to find by token or custom key.

- Defaults to token but a different key can be used instead.
- Ensures token value is retokenized before finding.
- Greatly simplifies what is used to find by.
Removed extraneous documentation.
Refactored hash value lookups to be fectched for improved debugging.
Refactored #scoped_token_conditions to #token_scope_conditions.
Refactored .rebuild_tokens to rebuild_tokens!
Updated macro method documentation.