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/sensors/buildjson.hpp b/sensors/buildjson.hpp
index c5aacc7..0a38b93 100644
--- a/sensors/buildjson.hpp
+++ b/sensors/buildjson.hpp
@@ -16,5 +16,5 @@
  * @param[in] data - the json data
  * @return a map of sensors.
  */
-std::map<std::string, struct SensorConfig>
+std::map<std::string, struct conf::SensorConfig>
     buildSensorsFromJson(const json& data);