Fixed issues where HTML comments inside style tag would hang Internet Explorer

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	CHANGELOG
Fix typo: occured -> occurred (#1489366)

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	installer/rcube_install.php
Update changelog
Updated Ukrainian translation as submitted by Vladislav
Fix text wrapping issue with long unwrappable lines (#1489371)

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	CHANGELOG
Fix address matching in Return-Path header on identity selection (#1489374)

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	CHANGELOG
Fix iframe onload for upload errors handling (#1489379)
Do not add css files to the page when body is empty, e.g. upload iframes
Fix vulnerability in handling _session argument of utils/save-prefs (#1489382)
Change default spell-check URI after Google suspended their spell service
Apply various IPAX fixes and add cleanup.sh script
Add IPAX configuration files
Temporary CSS fix