In some languages it's conventional not to insert a thousands
separator in numbers that are four digits long (1000-9999).
Rather than copy-paste the custom code to do this between 13 files,
introduce another option and have the base Language class handle it.
This also fixes an issue in several languages where this logic
previously would not work for negative or fractional numbers.
To implement this, a new option is added to MessagesXx.php files,
`$minimumGroupingDigits = 2;`, with the meaning as defined in
<http://unicode.org/reports/tr35/tr35-numbers.html>. It is a little
roundabout, but it could allow us to migrate the number formatting
(currently all custom code) to some generic library easily.
Bug: T177846
Change-Id: Iedd8de5648cf2de1c94044918626de2f96365d48
According to the typographical convention, a thousands separator
should not be inserted in numbers that are four digits long (between
1000 and 9999), unlike in English where it's usually acceptable.
This logic is currently implemented in LanguagePl::commafy().
Bug: T177846
Change-Id: I6dbd8febcf59000067cdd7d3c11111f2f77f4e66
