Merge pull request libgit2#6494 from libgit2/ethomson/clarify_readme

README: clarify the linking exception

Author: ethomson

README.md

@@ -25,8 +25,9 @@ and on Git hosting providers like [GitHub](https://github.com/),
 We perform the merge every time you click "merge pull request".
 
 `libgit2` is licensed under a **very permissive license** (GPLv2 with a special
-Linking Exception).  This basically means that you can link it (unmodified)
-with any kind of software without having to release its source code.
+Linking Exception). This means that you can link against the library with any
+kind of software without making that software fall under the GPL.
+Changes to libgit2 would still be covered under its GPL license.
 Additionally, the example code has been released to the public domain (see the
 [separate license](examples/COPYING) for more information).