Use the common WELS_CLIP3 macro instead of a custom reimplementation
Use an inline function instead of a macro for clipping which contains rand()

When using a macro, the macro parameters get evaluated
multiple times, which means that the rand() value compared
actually isn't the same that is used as return value.

This makes sure that clipping works as intended for the
random tests.
Increase the minimum frame size in a test with multiple spatial layers

Make sure the input frame size is large enough that the downsampled
layers also have a nonzero resolution.
Use the correct types instead of void pointers in function signatures

This gets rid of 50 lines of code with just casts of void pointers,
making the code shorter and clearer.
Merge pull request #1645 from mstorsjo/type-signatures

Use the correct types instead of void pointers in function signatures
Change the name and call logic of CheckRefPicturesComplete function.
cabac fix
Merge pull request #1640 from mstorsjo/fix-tests

Fix occasional failures in some tests
Merge pull request #1647 from HaiboZhu/Debug_Check_Ref_Picture_Complete

Change the name and call logic of CheckRefPicturesComplete function
Merge pull request #1646 from dongzha/cabacfix

cabac fix
Merge remote-tracking branch 'upstream/master' into travis.osx