Support PHP 8

This add supports for PHP 8, which in turn fixes #23.

Notice

The following version(s) of PHP have been deprecated in this release:

• 7.1

Fix Trailing Money Group Value In Sentence

Fixes #13.

Thanks to @flarpy for pinpointing the issue.

Improved And More Concise API

Features

• Support for a decimal number conversion.
• One converter object can be used to convert different numbers via $converter->convert(<number | dedimal>).
• Follow PHP standard naming convention.

Issues Resolved

• Fixes #6 - Undefined method ```ChangeCurrency()````.
• Fixes #7 - Issues with accuracy has been fixed, with a new conversion approach.
• Fixes #8 - Update .lock file.
• More tests.

Special Thanks

• @oza75 - Raising an issue for decimal support
• @mimidot - Raised an issue about accuracy and missing methods

Initial release

Features Added

• More Language translation added
• Added more numeric system support
• More detailed documentation