add UT for sim-SVC switch
reformat cpp files for next release
fix bug in set option return value
reformat cpp files for unit tests
Only use pthread_setname_np on Android >= 9 (2.3)

Older versions of Android don't have this function.
Merge pull request #1442 from mstorsjo/android-pthread-setname

Only use pthread_setname_np on Android >= 9 (2.3)
Merge pull request #1439 from sijchen/for_format

[Reformat] format cpp files for next release
Merge pull request #1440 from shihuade/APIUTV1.4

fix bug in set option return value
Merge pull request #1443 from dongzha/AddUTSwitch

add UT for sim-SVC layer switch
    fix a small range of slice idx
Merge pull request #1446 from sijchen/for_format

[Encoder] fix a small range of slice idx
roll back the file which is mis-formatted by astyle
Add casts to avoid warnings about comparison between signed and unsigned
Merge pull request #1448 from sijchen/for_format

roll back the file which is mis-formatted by astyle
fix a wrong range clip
fix names to keep consistent of style
improve UT to cover more cases under GetStatistics
Merge pull request #1450 from mstorsjo/avoid-warnings

Add casts to avoid warnings about comparison between signed and unsigned
Merge pull request #1451 from sijchen/for_format

Fixes and change naming
Add pkg-config file.
fix Rc int32_t bitrate overflow