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.
use the parameters set by app instead of the default values
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
remove typedef.h
Don't build all object files with -ZW, only the one that needs it

This reduces the build time from 69 s to 30 s, reduces the size of
the built wels.lib from 30 MB to 3.9 MB, and reduces the number of
warnings when building wels.lib.
Only use the -Gm option in desktop debug MSVC builds

This option conflicts with -ZW which is used in Windows Phone builds.
Merge pull request #765 from lyao2/scrollingUT

fix re-define issue
Merge pull request #768 from ruil2/enc_param

use the parameters set by app instead of the default values
fix the issue that long term reference frame is disable for screen
Merge pull request #769 from ruil2/enc_screen_1

fix the issue that long term reference frame is disable for screen
fix new sequence&EC order, and prefix parse bug
fix typedef re-define issue
Merge pull request #772 from lyao2/scrollingUT

this only solve the problem temporarily. but for the building of tests working, merge this first. 
we need to re-consider the including of typedef headers
Merge pull request #771 from huili2/newseqorder_prefixerror_bugfix

fix new sequence&EC order, and prefix parse bug
Merge pull request #766 from mstorsjo/reduce-msvc-runtime-flags

Don't build all object files with -ZW, only the one that needs it
Merge pull request #767 from mstorsjo/avoid-conflicting-msvc-options

Only use the -Gm option in desktop debug MSVC builds