Add CODEOWNERS file with USWDS admins

Adds a CODEOWNERS file establishing USWDS admins as global codeowners

.github/CODEOWNERS

@@ -0,0 +1,67 @@
+*       @uswds/admins
+
+# This is a comment.
+# 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.
+# *       @global-owner1 @global-owner2
+
+# 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.
+# *.js    @js-owner #This is an inline comment.
+
+# 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]
+
+# Teams can be specified as code owners as well. Teams should
+# be identified in the format @org/team-name. Teams must have
+# explicit write access to the repository. In this example,
+# the octocats team in the octo-org organization owns all .txt files.
+# *.txt @octo-org/octocats
+
+# 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
+
+# In this example, any change inside the `/scripts` directory
+# will require approval from @doctocat or @octocat.
+# /scripts/ @doctocat @octocat
+
+# In this example, @octocat owns any file in a `/logs` directory such as
+# `/build/logs`, `/scripts/logs`, and `/deeply/nested/logs`. Any changes
+# in a `/logs` directory will require approval from @octocat.
+# **/logs @octocat
+
+# In this example, @octocat owns any file in the `/apps`
+# directory in the root of your repository except for the `/apps/github`
+# subdirectory, as its owners are left empty.
+# /apps/ @octocat
+# /apps/github
+
+# In this example, @octocat owns any file in the `/apps`
+# directory in the root of your repository except for the `/apps/github`
+# subdirectory, as this subdirectory has its own owner @doctocat
+# /apps/ @octocat
+# /apps/github @doctocat