pw_cpu_exception: Add CPU exception module

This change introduces pw_cpu_exception, a facade that provides a
high-level interface for handling CPU exceptions.

Change-Id: I1f98ac82dd54040448b2e2ac32a392c49cb6dfba
diff --git a/pw_cpu_exception/BUILD b/pw_cpu_exception/BUILD
new file mode 100644
index 0000000..24e3a2a
--- /dev/null
+++ b/pw_cpu_exception/BUILD
@@ -0,0 +1,24 @@
+# Copyright 2019 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.
+
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])  # Apache License 2.0
+
+filegroup(
+    name = "pw_cpu_exception",
+    srcs = [
+        "public/pw_cpu_exception/cpu_exception.h",
+    ],
+)