This commit deprecates "--unstable" flag.
When "--unstable" flag is encountered a warning like this is printed:
```
The `--unstable` flag is deprecated, use granular `--unstable-*` flags instead.
Learn more at: https://docs.deno.com/runtime/manual/tools/unstable_flags
```
When "--unstable" flag is used and an unstable API is called an
additional warning like this is printed for each API call:
```
The `Deno.dlopen` API was used with `--unstable` flag. The `--unstable` flag is deprecated, use granular `--unstable-ffi` instead.
Learn more at: https://docs.deno.com/runtime/manual/tools/unstable_flags
```
When no "--unstable-*" flag is provided and an unstable API is called
following
warning is issued before exiting:
```
Unstable API 'Deno.dlopen'. The `--unstable-ffi` flag must be provided.
```
---------
Signed-off-by: Divy Srivastava <dj.srivastava23@gmail.com>
Signed-off-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Co-authored-by: Divy Srivastava <dj.srivastava23@gmail.com>
Co-authored-by: Asher Gomez <ashersaupingomez@gmail.com>
