fix some bugs of EC
bug fix of EC_copy
Merge pull request #762 from huili2/ec_ut_bugfix

bug fix of EC_copy, it fixes the memory issue  for decoder EC Unit Test which may lead crash.
Remove useless code
Merge pull request #763 from huili2/ec_bug_fix

fix some bugs of EC
Merge pull request #764 from dongzha/Deblock

Remove useless code