Implement network factory reset in network_manager

This commit implements a factory reset interface for the BMC
network. This factory reset is accomplished by removing any
/etc/systemd/network/*.network files, then writing new ones
configured for DHCP for each known interface.

Resolves openbmc/openbmc#1575

Change-Id: Ic006cd43fb336029479cffa783b56ab91e0339bd
Signed-off-by: Michael Tritz <mtritz@us.ibm.com>
diff --git a/Makefile.am b/Makefile.am
index 75c49e6..29517f9 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -12,6 +12,7 @@
 
 noinst_HEADERS = \
 		ethernet_interface.hpp \
+		network_config.hpp \
 		network_manager.hpp \
 		ipaddress.hpp \
 		types.hpp
@@ -19,6 +20,7 @@
 phosphor_network_manager_SOURCES = \
 		ethernet_interface.cpp \
 		ipaddress.cpp \
+		network_config.cpp \
 		network_manager.cpp \
 		network_manager_main.cpp \
 		xyz/openbmc_project/Network/VLAN/Create/server.cpp \
@@ -65,4 +67,3 @@
 	@mkdir -p `dirname $@`
 	$(SDBUSPLUSPLUS) -r $(srcdir) interface server-header xyz.openbmc_project.Network.IP.Create > $@
 	sed -i '5i #include \"xyz\/openbmc_project\/Network\/IP\/server.hpp\"' $@
-