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/test/pid_json_unittest.cpp b/test/pid_json_unittest.cpp
index 098d9da..c8a1f61 100644
--- a/test/pid_json_unittest.cpp
+++ b/test/pid_json_unittest.cpp
@@ -8,8 +8,8 @@
     // There is a zone key, but it's empty.
     // This is technically invalid.
 
-    std::map<int64_t, PIDConf> pidConfig;
-    std::map<int64_t, struct ZoneConfig> zoneConfig;
+    std::map<int64_t, conf::PIDConf> pidConfig;
+    std::map<int64_t, struct conf::ZoneConfig> zoneConfig;
 
     auto j2 = R"(
       {
@@ -27,8 +27,8 @@
 {
     // Parse a valid configuration with one zone and one PID.
 
-    std::map<int64_t, PIDConf> pidConfig;
-    std::map<int64_t, struct ZoneConfig> zoneConfig;
+    std::map<int64_t, conf::PIDConf> pidConfig;
+    std::map<int64_t, struct conf::ZoneConfig> zoneConfig;
 
     auto j2 = R"(
       {