auto merge of #15267 : ruud-v-a/rust/patch-1, r=huonw

[This commit](25fe2ca#diff-04c6e90faac2675aa89e2176d2eec7d8R57) forgot to remove one line.

Author: bors

README.md

@@ -54,7 +54,6 @@ documentation.
     When complete, `make install` will place several programs into
     `/usr/local/bin`: `rustc`, the Rust compiler, and `rustdoc`, the
     API-documentation tool.
-    system.
 3. Read the [tutorial].
 4. Enjoy!