LDC 1.30.0-beta1

[kinke]

Glad to announce the first beta for LDC 1.30. Major changes:

* Based on D 2.100.0.
* LLVM for prebuilt packages bumped to v14.0.3. All target 
architectures supported by LLVM are enabled now.
* Dropped LDC ltsmaster (v0.17.x) as supported host compiler. 
Like DMD, the min D version for bootstrapping is v2.079 (or GDC 
v9.x) now.
* Dropped support for LLVM < 9.
* New prebuilt **universal** macOS package, runnable on both 
x86_64 and arm64, and enabling x86_64/arm64 macOS/iOS 
cross-compilation targets out of the box.
   **Note**: avoid using an x86_64-only dub and use the bundled 
dub executable instead.

Full release log and downloads: 
https://github.com/ldc-developers/ldc/releases/tag/v1.30.0-beta1

Please help test, and thanks to all contributors & sponsors!