UefiCpuPkg/CpuExceptionHandlerLib: Add DumpCpuContext() implementation

Export DumpCpuCotext() to display CPU Context. We will invoke
PeCoffGetEntrypointLib's PeCoffSerachImageBase() to get PE/COFF image base.
Display exception data bit value for page fault exception.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

UefiCpuPkg/Library/CpuExceptionHandlerLib/DxeException.c

@@ -1,7 +1,7 @@
 /** @file
   CPU exception handler library implemenation for DXE modules.
 
-  Copyright (c) 2013 - 2016, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2013 - 2017, Intel Corporation. All rights reserved.<BR>
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
   which accompanies this distribution.  The full text of the license may be found at
@@ -19,11 +19,6 @@
 
 CONST UINTN    mDoFarReturnFlag  = 0;
 
-//
-// Image align size for DXE/SMM
-//
-CONST UINTN      mImageAlignSize = SIZE_4KB;
-
 RESERVED_VECTORS_DATA       mReservedVectorsData[CPU_EXCEPTION_NUM];
 EFI_CPU_INTERRUPT_HANDLER   mExternalInterruptHandlerTable[CPU_EXCEPTION_NUM];
 UINTN                       mEnabledInterruptNum = 0;