Move blog guidelines out of "core".

In preparation to remove the core chapter.

Author: ehuss

book.toml

@@ -50,3 +50,4 @@ curly-quotes = true
 "chat/zulip/index.html" = "/platforms/zulip/index.html"
 "chat/zulip.html" = "/platforms/zulip.html"
 "platforms/zulip/triagebot.html" = "/triagebot/index.html"
+"core/blogs.html" = "/platforms/blogs.html"

src/SUMMARY.md

@@ -8,6 +8,7 @@
   - [GitHub](./platforms/github.md)
   - [Zulip](./platforms/zulip.md)
       - [Moderation](./platforms/zulip/moderation.md)
+  - [Blogs](./platforms/blogs.md)
 - [Triagebot](./triagebot/README.md)
     - [Agenda Generator](./triagebot/agenda.md)
     - [Issue Assignment](./triagebot/issue-assignment.md)
@@ -33,7 +34,6 @@
     - [Zulip Meeting Management](./triagebot/zulip-meeting.md)
     - [Zulip Notifications](./triagebot/zulip-notifications.md)
 - [Core](./core/README.md)
-    - [Rust Blog Guidelines](./core/blogs.md)
 - [Community](./community/README.md)
     - [State of Rust Survey FAQ](./community/survey-faq.md)
 - [Compiler](./compiler/README.md)