Contribute back our version of the flag of Croatia.

[Wyatt OʼDay]

See commit 899dcea

Update flag of Croatia to use correct colors as specified by their government. Namely, use the Pantone colors specified here: https://web.archive.org/web/20120208064423/http://www.sabor.hr/lgs.axd?t=16&id=19045

Which matches the actual colors of the flag used by the government in real life (i.e. at the U.N.).

crvena (red), Pantone 186 C: https://www.pantone.com/color-finder/186-c

Hex: #C8102E

plava (blue), PANTONE Process Cyan C, https://www.pantone.com/color-finder/Process-Cyan-C

Hex: #00A3E0

modra (navy blue), PANTONE Reflex Blue C, https://www.pantone.com/color-finder/reflex-blue-c

Hex: #001489

zuta (yellow), PANTONE 108 C, https://www.pantone.com/color-finder/108-C

Hex: #FEDB00

These changes should be contributed back to Wiki Commons: https://commons.wikimedia.org/wiki/File:Flag_of_Croatia.svg