build: General build refactoring

Add vars.mk for variable sharing across makefiles.
Stub and rename example YAML file and template.
  Content to be re-introduced as support is added.
Move generated C++ to a header file.
Add input YAML path option to configure.

Change-Id: Ia06e392e8b120b1e1d8614046064fa432a6f9e18
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/src/example/example.yaml b/src/example/example.yaml
new file mode 100644
index 0000000..5a798e9
--- /dev/null
+++ b/src/example/example.yaml
@@ -0,0 +1 @@
+# Example PDM configuration file.
diff --git a/src/example/monitoring_defs.yaml b/src/example/monitoring_defs.yaml
deleted file mode 100644
index 04629db..0000000
--- a/src/example/monitoring_defs.yaml
+++ /dev/null
@@ -1,55 +0,0 @@
-# Example sensor monitoring definition
-groups:
-    - name: fan_zone_group
-      description: Group of fan tach sensors
-      type: fan_tach
-      members:
-          - fan0
-          - fan1
-          - fan2
-          - fan3
-
-triggers:
-    - name: app_start
-      description: The sensor group manager application started
-      type: start
-    - name: properties_changed
-      description: A property change dbus signal
-      type: signal
-      signature:
-          interface: org.freedesktop.DBus.Properties
-          member: PropertiesChanged
-
-conditions:
-    - name: fans_at_or_above_speed
-      type: countAtOrAbove
-      interface: xyz.openbmc_project.Sensor.Value
-      property: Value
-      parameters:
-          group: name
-          group: member
-          count: 3
-          value:
-              value: 8000
-              type: int64
-
-actions:
-    - name: log_error
-      type: log_error
-      parameters:
-          message: string
-
-events:
-    - name: fans_over_speed
-      groups:
-          - fan_zone_group
-      triggers:
-          - name: app_start
-            conditions:
-                - fans_at_or_above_speed
-          - name: properties_changed
-            conditions:
-                - fans_at_or_above_speed
-      actions:
-          - name: log_error
-            message: "ERROR: Number of fans at or above 8000rpms reached"