a couple more small changes

Author: mark-i-m

src/SUMMARY.md

@@ -5,8 +5,8 @@
 ---
 
 - [Part 1: Building, debugging, and contributing to Rustc](./part-1-intro.md)
-    - [About the compiler team](./compiler-team.md)
     - [Getting Started](./getting-started.md)
+    - [About the compiler team](./compiler-team.md)
     - [How to Build and Run the Compiler](./building/how-to-build-and-run.md)
         - [Suggested Workflows](./building/suggested.md)
         - [Bootstrapping](./building/bootstrapping.md)

src/getting-started.md

@@ -272,7 +272,8 @@ After that, the feature gate can be removed and the feature turned on for all us
 
 As mentioned above, Rust has strong backwards-compatibility guarantees. To this
 end, we are reluctant to make breaking changes. However, sometimes they are
-needed to correct compiler bugs (e.g. code that compiled but should not).
+needed to correct compiler bugs (e.g. code that compiled but should not) or
+make progress on some features.
 
 Depending on the scale of the breakage, there are a few different actions that
 can be taken.  If the reviewer believes the breakage is very minimal (i.e. very