Add x86 64bit asm code for downsample
Ignore files produced by the new binary comparison tool
Remove unnecessarily set AdditionalLibraryDirectories

Some of these even pointed to directories that don't exist (and
don't get created during the build process).
    interface update
Remove some manually set options, that are set to the default value

These are the only places where these options are overridden.
Don't set path to a precompiled header - precompiled headers are disabled
Set DebugInformationFormat consistently in all projects

Use the "Program Database (/Zi)" in release mode and in debug
mode for x64, use "Program Database for Edit & Continue (/ZI)"
in debug mode for Win32.

This is how new visual studio projects are set by default.
Don't set custom build options for VCMIDLTool

This tool isn't even used in the build (and thus, these settings
aren't even visible in the IDE).
Avoid repeated code for getting the android toolchain prefix
fix bug when temporal layer changes
Only build the needed binaries in run_PrepareAllTestData.sh

Previously this did a full make, including all of gtest and the unit
test suite. This was done before every build, even for the binary
comparison tests which doesn't use the unit test.

This reduces the runtime of run_PrepareAllTestData.sh from 52 to 10
seconds in one setup.
Merge pull request #1123 from mstorsjo/remove-unused-pch-path

Don't set path to a precompiled header - precompiled headers are disabled
Merge pull request #1120 from mstorsjo/remove-nonexistent-paths

Remove unnecessarily set AdditionalLibraryDirectories
Merge pull request #1122 from mstorsjo/remove-hardcoded-defaults

Remove some manually set options, that are set to the default value
Merge pull request #1124 from mstorsjo/consistent-debug-options

Set DebugInformationFormat consistently in all projects
Merge pull request #1125 from mstorsjo/remove-unused-options

Don't set custom build options for VCMIDLTool
Merge pull request #1127 from ruil2/temporal_bug_fix

fix bug when temporal layer changes
Use $(OutDir) instead of hardcoding the directory name

This is how it is done in the other projects.
Set optimizer options in WelsVP similarly to the other encoder projects
Remove stray optimization options from the WelsEncPlus project

There's not much performance critical code within this lib, all
the performance critical code in the encoder is in WelsEncCore and
WelsVP, so there's little point in having an extra odd option enabled
here.