Add supported versions info to README

README.md

@@ -32,17 +32,22 @@ This crate provides high-level, idiomatic Rust bindings for GDAL.
 To do that, it uses [`gdal-sys`](gdal-sys) internally, a low-level interface to the GDAL C library, which is generated using [`bindgen`](https://rust-lang.github.io/rust-bindgen/).
 Using the `gdal-sys` crate directly is normally not needed, but it can be useful in order to call APIs that have not yet been exposed in `gdal`.
 
+## Version support
+
+As a general rule, only GDAL versions in Ubuntu LTS-1 (previous LTS version, that is, GDAL 3.0 in 20.04 at this moment) are supported.
+`gdal-sys` might support earlier versions using the `bindgen` feature flag, but `gdal` does not.
+
 Building this crate assumes a compatible version of GDAL is installed with the corresponding header files and shared libraries.
-This repository includes pre-generated bindings for GDAL 2.4 through 3.6 (see the`gdal-sys/prebuilt-bindings` directory).
-If you're compiling against a later version of GDAL, you can enable the `bindgen` feature flag to have new bindings generated on the fly. 
+This repository includes pre-generated bindings for GDAL 3.0 through 3.8 (see the`gdal-sys/prebuilt-bindings` directory).
+If you're compiling against another version of GDAL, you can enable the `bindgen` feature flag to have the bindings generated on the fly. 
 
 ## Community
 
 This crate is part of the expansive (and expanding!) [`georust`](https://georust.org/) organization. Come join our discussions on [Discord](https://discord.gg/Fp2aape)!
 
 ## Contributing
 
-This crate continues to evolve, and PRs are welcome. Make sure you are comfortable with the [Code of Conduct](CODE_OF_CONDUCT.md) and [License](LICENSE.txt) before submitting a PR.
+This crate continues to evolve, and PRs are always welcome. Make sure you are comfortable with the [Code of Conduct](CODE_OF_CONDUCT.md) and [License](LICENSE.txt) before submitting a PR.
 
 ## License