docs: Document when environment() was added (#5178) [skip ci]

The environment() function was added in 0.35.0 (which contains a2e7ebc5, containing the actual addition)
6 years ago · 2a030e33f3
parent f8afcd59e0
commit 2a030e33f3
1 changed files with 2 additions and 1 deletions
--- a/docs/markdown/Reference-manual.md
+++ b/docs/markdown/Reference-manual.md
@ -456,7 +456,8 @@ Print the argument string and halts the build process.
    environment_object environment()
 ```

-Returns an empty [environment variable object](#environment-object).
+Returns an empty [environment variable object](#environment-object). Added in
+0.35.0.

 ### executable()