Kirill Bobyrev 8080ea4c4b [clangd] Enable reflection for clangd-index-server
This allows sending requests through CLI and more debugging
opportunities. Example:

```bash
$ grpc_cli ls localhost:50051
clang.clangd.remote.v1.SymbolIndex
grpc.reflection.v1alpha.ServerReflection
grpc.health.v1.Health
```
2021-03-10 09:07:39 +01:00
..

See docs/CMake.html for instructions on how to build LLVM with CMake.