support specifying --d-versions ...

Usually you should prefer using configurations and build types, but
sometimes, especially when wrapped in other build tools or when
supporting e.g. different target platforms on the same target
architecture and configuration, you may want to manually manage certain
versions.

Add support for coverage at compile-time (CTFE)

Add build type syntax

Update lists of build types in Sublime generator and fish shell completion

update fish completion ...

- add clean-caches
- fix typo

Adding FISH shell completion