Basic CMake build

- Automatically add simple modules with pw_auto_add_simmple_module.
- Define libraries in a module with pw_add_module_library.
- Define tests and test groups with pw_add_test and
  pw_add_test_to_groups.
- Tests execute with full Ninja dependency resolution, as in the GN
  build.
- Add CMakeLists.txt for existing modules.
- Currently there is no support for targets, but these libraries would
  be trivial to integrate with an existing CMake build.

Change-Id: If73d8b61bce88f91141737eb773f1ebce3a7676e
diff --git a/pw_status/CMakeLists.txt b/pw_status/CMakeLists.txt
new file mode 100644
index 0000000..132c41e
--- /dev/null
+++ b/pw_status/CMakeLists.txt
@@ -0,0 +1,15 @@
+# Copyright 2020 The Pigweed Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+
+pw_auto_add_simple_module(pw_status)