Setup default stdout to utf-8

Error occurred when Linux Language environment variables is set to "zh_CN.UTF-8": File "/usr/local/lib/python3.6/dist-packages/gpustat/core.py", line 397, in print_to fp.write(''.join(reps)) UnicodeEncodeError: 'ascii' codec can't encode character '\xb0' in position 61: ordinal not in range(128) steps to recurrent: 1. set the LANG in Linux command line: ``` export LANG='zh_US.UTF-8' ``` 2. run `gpustat` 3. restult: ``` Traceback (most recent call last): File "/usr/local/bin/gpustat", line 8, in <module> sys.exit(main()) File "/usr/local/lib/python3.6/dist-packages/gpustat/cli.py", line 217, in main print_gpustat(**vars(args)) File "/usr/local/lib/python3.6/dist-packages/gpustat/cli.py", line 82, in print_gpustat gpu_stats.print_formatted(sys.stdout, **kwargs) File "/usr/local/lib/python3.6/dist-packages/gpustat/core.py", line 716, in print_formatted term=t_color) File "/usr/local/lib/python3.6/dist-packages/gpustat/core.py", line 397, in print_to fp.write(''.join(reps)) UnicodeEncodeError: 'ascii' codec can't encode character '\xb0' in position 61: ordinal not in range(128) ``` Runtime environment: Linux 18.04 Kernel 4.15.0-212-generic Python 3.6.9 Solution: **Setup default stdout to utf-8** as commit