parser:  Add more skeleton boilerplate

Add a basic load/render skeleton.
Add docstrings.
Add multiple file parsing.
Steal indent utility from phosphor-inventory-manager.
Scan YAML for syntax and discard.

Change-Id: I48e5a3923dc1fadceae6241dd6f757388a2f1c51
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/src/Makefile.am b/src/Makefile.am
index 44590c2..6afb7b9 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -19,4 +19,4 @@
 CLEANFILES = generated.cpp
 
 generated.cpp:
-	$(AM_V_GEN)$(PYTHON) ${srcdir}/pdmgen.py -y ${srcdir}/example/monitoring_defs.yaml -o ${builddir}
+	$(AM_V_GEN)$(PYTHON) ${srcdir}/pdmgen.py generate-cpp -d ${srcdir}/example -o ${builddir}