Synchronize D 2.101.0 release with tooling please

[ryuukk_]

Please think about tooling before doing the release

As usual tooling was completely ignored

DUB merged stable without ImportC support.. [1]

- DUB: needs ImportC support PR: [2]

- DCD: needs to pick up bitfield support from recent libdparse PR 
[3]


So we can ensure users will have a great experience


[1] - https://github.com/dlang/dub/pull/2529

[2] - https://github.com/dlang/dub/pull/2522

[3] - https://github.com/dlang-community/libdparse/pull/476