Added CODEOWNERS to require PRBR code review (FreeRTOS#364)

Author: cobusve

.github/CODEOWNERS

@@ -0,0 +1,39 @@
+# Each line is a file pattern followed by one or more owners.
+
+# These owners will be the default owners for everything in
+# the repo. Unless a later match takes precedence,
+# @global-owner1 and @global-owner2 will be requested for
+# review when someone opens a pull request.
+*      @FreeRTOS/pr-bar-raiser
+
+# Order is important; the last matching pattern takes the most
+# precedence. When someone opens a pull request that only
+# modifies JS files, only @js-owner and not the global
+# owner(s) will be requested for a review.
+# *.c FreeRTOS/pr-bar-raiser
+
+# You can also use email addresses if you prefer. They'll be
+# used to look up users just like we do for commit author
+# emails.
+# *.go [email protected]
+
+# In this example, @doctocat owns any files in the build/logs
+# directory at the root of the repository and any of its
+# subdirectories.
+# /build/logs/ @doctocat
+
+# The `docs/*` pattern will match files like
+# `docs/getting-started.md` but not further nested files like
+# `docs/build-app/troubleshooting.md`.
+# docs/*  [email protected]
+
+# In this example, @octocat owns any file in an apps directory
+# anywhere in your repository.
+# apps/ @octocat
+
+# In this example, @doctocat owns any file in the `/docs`
+# directory in the root of your repository and any of its
+# subdirectories.
+# /docs/ @doctocat
+
+