Encode insert tags in the Input class
Fix a potential directory traversal vulnerability
Use Input::postUnsafeRaw() to hash and compare passwords
Do not use the translated labels in the exception message
Store the unfiltered SMTP password
Merge branch 'hotfix/security-fixes' into release/3.4.0

Conflicts:
	contao/install.php
	contao/password.php
	system/docs/CHANGELOG.md
	system/modules/core/classes/Theme.php
	system/modules/core/dca/tl_settings.php
	system/modules/core/library/Contao/Controller.php
	system/modules/core/library/Contao/User.php
	system/modules/core/modules/ModuleSearch.php