Expand conf namespace

Put rest of conf.hpp in the conf namespace. This is
largely a sed replace, and wrapping from_json in
conf namespace as it failed to build.

Change-Id: I9fe5c7b2fface44618c43af2367035afc39bcb64
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/pid/builder.hpp b/pid/builder.hpp
index 2b28663..e500503 100644
--- a/pid/builder.hpp
+++ b/pid/builder.hpp
@@ -8,6 +8,6 @@
 #include <unordered_map>
 
 std::unordered_map<int64_t, std::unique_ptr<PIDZone>>
-    buildZones(std::map<int64_t, PIDConf>& zonePids,
-               std::map<int64_t, struct ZoneConfig>& zoneConfigs,
+    buildZones(std::map<int64_t, conf::PIDConf>& zonePids,
+               std::map<int64_t, struct conf::ZoneConfig>& zoneConfigs,
                SensorManager& mgr, sdbusplus::bus::bus& modeControlBus);