Revert changes to raw CSS @imports
Due to unintended disruption this change has been reverted in favour of a language level revision to CSS imports to be implemented at a future date.
Note to implementors: this removes the
sass_option_push_import_extension API added in 3.5.4. Apologies for the disruption.
- Support hex colors with alpha channels (@xzyfer, #2674)
- Add a
sass_option_push_import_extensionC-API (@xzyfer, #1964)