Remove unreleased versions from CHANGELOG.md

Signed-off-by: Geert Eltink <[email protected]>

Author: geerteltink

CHANGELOG.md

@@ -24,28 +24,6 @@ All notable changes to this project will be documented in this file, in reverse
 
 - Nothing.
 
-## 1.8.1 - TBD
-
-### Added
-
-- Nothing.
-
-### Changed
-
-- Nothing.
-
-### Deprecated
-
-- Nothing.
-
-### Removed
-
-- Nothing.
-
-### Fixed
-
-- Nothing.
-
 ## 1.8.0 - 2019-03-05
 
 ### Added