internal miner: move 2 globals from main to miner

- moves 2 global variables from main.cpp/h to miner.cpp/h
- also removes 2 unneded includes in miner.cpp, that come from miner.h
  already

src/miner.cpp

@@ -3,15 +3,11 @@
 // Distributed under the MIT/X11 software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
-#include "core.h"
-#include "wallet.h"
 #include "miner.h"
 #include "main.h"
 
-
-
-
-
+double dHashesPerSec = 0.0;
+int64 nHPSTimerStart = 0;
 
 //////////////////////////////////////////////////////////////////////////////
 //