GitHub code owners

The project adapted to GitHub's code owners  feature. This allows to
define matching pattern for project paths to automatically add all
required reviewers of the core team and contributors to new PRs.

See GitHub Help (2) for more details.

References:
  (1) https://github.com/blog/2392-introducing-code-owners
  (2) https://help.github.com/articles/about-codeowners

Epic: GH-33
Depends on GH-49
Resolves GH-43

.github/CODEOWNERS

@@ -0,0 +1,19 @@
+# Copyright (C) 2017-present Arctic Ice Studio <[email protected]>
+# Copyright (C) 2017-present Sven Greb <[email protected]>
+#
+# Project:    snowsaw
+# Repository: https://github.com/arcticicestudio/snowsaw
+# License:    MIT
+
+# Configuration for the GitHub feature to automatically request reviews from
+# the code owners when a pull request changes any owned files.
+#
+# References:
+#   https://github.com/blog/2392-introducing-code-owners
+#   https://help.github.com/articles/about-codeowners
+
+# +----------------------+
+# + Core Team Code Owner +
+# +----------------------+
+* @arcticicestudio
+* @svengreb