Filters: number() and bytes() with locale round half up like without locale

[vosikar]

• bug fix, https://forum.nette.org/cs/36983-filtr-number-zaokrouhlovani
• BC break? yes - only rounding of exact halves with a locale set
• doc PR: not needed

With a locale set |number and |bytes use NumberFormatter, which rounds half-even by default. Without a locale the number_format() / round() is used, which rounds half away from zero. The formatter now uses ROUND_HALFUP, so both round the same way. Covered by new tests.

{9.105|number:2} {* 9.11 without locale, 9,10 with cs *}