Fixed imgcodecs tests

- Imgcodecs_Image, write_imageseq - assuming JPEG images have losses
- Imgcodecs_Drawing, c_regression - replaced assert calls
- Imgcodecs_Drawing - exact comparison with reference image
Disabled videoio_video_prop_fps test

This test does not return correct values with some software configurations.
Possible problem with ffmpeg on buildbot's linux-slave.
Merge pull request #3361 from mshabunin:fix-drawing