Add a basic KSP Symbol Processor for Glide

[copybara-service]

Add a basic KSP Symbol Processor for Glide

This library only implements support for basic configuration of Glide. Like the
Java version it can detect and merge multiple LibraryGlideModules and a single
AppGlideModule. The merged output (GeneratedAppGlideModule) will then be
called via reflection to configure Glide when Glide is first used.

Unlike the Java version this processor has no support for:

1. Extensions
2. Including or Excluding LibraryGlideModules that are added via AndroidManifest registration
3. Generated Glide, RequestOptions, RequestBuilder, and RequestManager
   overrides.
4. Excluding LibraryGlideModules that are added via annotations

I suspect very few people use the first two missing features and so,
barring major objections, those features will be only available via the
Java processor and in the very long run, deprecated. Kotlin extension
functions can provide the same value with less magic and complexity as
Extensions. AndroidManifest registrtion has been deprecated for years.

For #3 ideally we do not support these generated overrides either. Their
only real purpose was to expose the functionality provided by
Extensions. The one caveat is that our documentation has encouraged
their use in the past. If we remove support instantly, it may complicate
migration.

I will support #4, but in a future change. This one is large enough
already.