update the googleurl readme to reflect support for c++14 or later versions

Signed-off-by: Yifan Yang <needyyang@google.com>

README.md

diff --git a/README.md b/README.md
index e58ff05..25cb9d5 100644
--- a/README.md
+++ b/README.md
@@ -6,8 +6,8 @@
 [QUICHE](https://quiche.googlesource.com/quiche/+/refs/heads/master), but can be
 also used by other projects that use Bazel.
 
-In order to be used successfully, `-std=c++14` and `-fno-strict-aliasing`
-compile flags are required.
+In order to be used successfully, c++14 or later and `-fno-strict-aliasing`
+compile flag are required.
 
 For questions, contact <proto-quic@chromium.org>.
 
@@ -17,7 +17,8 @@
 the following commands in the root of the checkout:
 
 1. `copybara copy.bara.sky import <path-to-chrome>/src --folder-dir .`
-1. `bazel test --cxxopt="-std=c++14" //...`
+1. `bazel test --cxxopt="-std=c++14" //...` 
+   (c++14 is replacible with later c++ versions)
 1. Fix all of the compilation errors, potentially modifying the BUILD files and
    the polyfill headers in `polyfill/` as appropriate.
 1. Check the new version into Git.