Fail gracefully for files that cant be opened using utf-8

[jayvdb]

It would be great if enmerkar could skip files which can not be opened as text, with a warning.

I have three docx/xlsx files causing errors like below, encountered if I use mapping [django: */templates/**.*]. To avoid this it seems I need to specify lots of sections in my babel.cfg mapping file for all the other filetypes I want processed.

extracting messages from common\templates\common\docx\WIN_TEMPLATE.docx
Traceback (most recent call last):
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\Scripts\pybabel.exe\__main__.py", line 7, in <module>
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\babel\messages\frontend.py", line 929, in main
    return CommandLineInterface().run(sys.argv)
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\babel\messages\frontend.py", line 853, in run
    return cmdinst.run()
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\babel\messages\frontend.py", line 481, in run
    for filename, lineno, message, comments, context in extracted:
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\babel\messages\extract.py", line 157, in extract_from_dir
    dirpath=absname,
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\babel\messages\extract.py", line 212, in check_and_call_extract_file
    strip_comment_tags=strip_comment_tags
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\babel\messages\extract.py", line 244, in extract_from_file
    options, strip_comment_tags))
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\babel\messages\extract.py", line 325, in extract
    for lineno, funcname, messages, comments in results:
  File "C:\Users\vandjohn\Downloads\WPy64-3771\python-3.7.7.amd64\lib\site-packages\enmerkar\extract.py", line 52, in extract_django
    text = fileobj.read().decode(encoding)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xa1 in position 14: invalid start byte