BaseTools: Refactor python print statements

Refactor print statements to be compatible with python 3.
Based on "futurize -f libfuturize.fixes.fix_print_with_import"

Contributed-under: TianoCore Contribution Agreement 1.1
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Yonghong Zhu <yonghong.zhu@intel.com>

BaseTools/Scripts/PackageDocumentTools/plugins/EdkPlugins/basemodel/doxygen.py

@@ -11,6 +11,7 @@
 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #
 
+from __future__ import print_function
 import os
 
 from message import *
@@ -446,4 +447,4 @@ if __name__== '__main__':
     p.AddPage(Page('PCD', 'pcds'))
 
     df.Generate()
-    print df
+    print(df)