Move resolver public headers to separate include path

Additionally rename functions and structs to eliminate those ugly
underscores from the public API (with the notable exception of
__res_params, which will come in its own separate change to keep this
one from growing too large).

Test: build, flash, then 'atest netd_integration_test'
Change-Id: I7e9b0ee6cdbec889e9c35b5a17b5daa65533686e
diff --git a/server/RouteController.cpp b/server/RouteController.cpp
index 6774fd5..3ffe561 100644
--- a/server/RouteController.cpp
+++ b/server/RouteController.cpp
@@ -33,13 +33,13 @@
 #include "NetlinkCommands.h"
 #include "UidRanges.h"
 
-#include "android-base/file.h"
+#include <android-base/file.h>
 #include <android-base/stringprintf.h>
 #define LOG_TAG "Netd"
 #include "log/log.h"
 #include "logwrap/logwrap.h"
+#include "netid_client.h"
 #include "netutils/ifc.h"
-#include "resolv_netid.h"
 
 using android::base::StringPrintf;
 using android::base::WriteStringToFile;