hg: jdk/sandbox: 8247976: Update HotSpot Style Guide for C++14 adoption

[chris.hegarty at oracle.com]

Changeset: 0b2131635c06
Author:    kbarrett
Date:      2020-07-27 22:19 -0400
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/0b2131635c06

8247976: Update HotSpot Style Guide for C++14 adoption
Summary: Update and move style guide from wiki to jdk repo.
Reviewed-by: jrose, stefank, dholmes, mikael, stuefe, kvn

+ doc/hotspot-style.html
+ doc/hotspot-style.md