Minor fix to pdf rule
Add regex for index based string formatting.

* Add locale configs
* Cleanup header file
Add kvc as dependency for querying locale key-values
Refactor data generators

Remove all data formats from modules, and use faker:fetch and fakerl:parse for managing data formats.
Add default locale file: en.yml

Use default locale( 'en.yml' ) for generating data,

To add new locale, add {{locale_name}}.yml to the 'priv/locales' directory.
All locale files must be adhere to the same format as the default 'en.yml' locale config.
If a locale does not have a section or key, the default locale section or key is used instead.
Add credit card generator
Add jobs generator
Add phone number generator
Add user agent generator