A simple handy class to format numbers, provides 2 main ways of format numbers:
1) `comma_grouped` - 5678 => "5,678"
2) `shorten_number` - 5678 => "5.6k"
Example Usage
// Get Number Formatter instance
NumberFormatter nf = NumberFormatter.getInstance(MainActivity.this);
nf.shorten_number(1234);
nf.comma_grouped(1234);
// Use with static methods
NumberFormatter.get_shortened_number(1234);
NumberFormatter.get_comma_grouped_number(MainActivity.this, 1234);