FindBZip2: Add Windows library names emitted from bzip2 1.0.6 makefile

As of release 1.0.6, the bzip2 distribution includs a makefile for nmake
on Windows that emits library names of the form `libbz2.lib`.

Modules/FindBZip2.cmake

@@ -45,8 +45,8 @@ set(_BZIP2_PATHS PATHS
 find_path(BZIP2_INCLUDE_DIR bzlib.h ${_BZIP2_PATHS} PATH_SUFFIXES include)
 
 if (NOT BZIP2_LIBRARIES)
-    find_library(BZIP2_LIBRARY_RELEASE NAMES bz2 bzip2 ${_BZIP2_PATHS} PATH_SUFFIXES lib)
-    find_library(BZIP2_LIBRARY_DEBUG NAMES bz2d bzip2d ${_BZIP2_PATHS} PATH_SUFFIXES lib)
+    find_library(BZIP2_LIBRARY_RELEASE NAMES bz2 bzip2 libbz2 libbzip2 ${_BZIP2_PATHS} PATH_SUFFIXES lib)
+    find_library(BZIP2_LIBRARY_DEBUG NAMES bz2d bzip2d libbz2d libbzip2d ${_BZIP2_PATHS} PATH_SUFFIXES lib)
 
     include(${CMAKE_CURRENT_LIST_DIR}/SelectLibraryConfigurations.cmake)
     SELECT_LIBRARY_CONFIGURATIONS(BZIP2)