Revert "update lerp api in filters"

This reverts commit a8a21e5618023b2eda49ad013030479528635c54.
Revert "lerp: didn't work at all, now does"

This reverts commit a21435cb6fe163d6579f3fd3d42ad11c54037036.
Revert "update accela, ewma to use lerp class"

This reverts commit 7428b028ffd95c229c57f8089b97e6bd0af34339.
Revert "lerp class to simplify filter flow"

This reverts commit 5409f26675a444170b3a68fc9750742cc68aaa1d.