Add a basic "Getting Started" page for AOS documentation

Initially, just walk someone through setting up a basic ping/pong
application. There is a bunch of high-level design choices and reference
documentation still to write, but wanted to get something started.

Change-Id: I61dc0721e29f95bd96136c9c8f85751e81f440ab
Signed-off-by: James Kuszmaul <james.kuszmaul@bluerivertech.com>
diff --git a/documentation/aos/BUILD b/documentation/aos/BUILD
new file mode 100644
index 0000000..1cab16e
--- /dev/null
+++ b/documentation/aos/BUILD
@@ -0,0 +1,7 @@
+load("//tools/build_rules:mkdocs.bzl", "mkdocs")
+
+mkdocs(
+    name = "docs",
+    srcs = glob(["docs/*.md"]),
+    config = "mkdocs.yaml",
+)