Adopt `potodo` in Makefile

I found a tool named potodo that provides same functionalities with part of our current Makefile commands but has better format. We can consider adopting this tool in our Makefile (or even storing the output as a file and updating it whenever a PR is merged).

• Listing untranslated files

  • make todo

    > make todo           
    for file in *.po */*.po; do echo $(msgattrib --untranslated $file | grep ^msgid | sed 1d | wc -l ) $file; done | grep -v ^0 | sort -gr
    929 library/stdtypes.po
    790 library/os.po
    660 whatsnew/3.3.po
    633 library/curses.po
    577 c-api/typeobj.po
    555 whatsnew/3.7.po
    554 library/datetime.po
    539 whatsnew/3.5.po
    539 whatsnew/2.6.po
    518 whatsnew/3.2.po
    517 whatsnew/3.6.po
    ...
    

  • potodo

    > potodo
    # extending (3.17% done)
    
    - building.po                      0 /  23 (  0.0% translated)
    - embedding.po                     1 /  45 (  2.0% translated)
    - extending.po                     2 / 158 (  1.0% translated)
    - newtypes.po                      0 /  91 (  0.0% translated)
    - newtypes_tutorial.po             0 / 123 (  0.0% translated)
    - windows.po                       0 /  21 (  0.0% translated)
    
    
    # faq (10.27% done)
    
    - design.po                       13 / 141 (  9.0% translated), 2 fuzzy
    - extending.po                     0 /  60 (  0.0% translated)
    - general.po                      33 /  91 ( 36.0% translated)
    - gui.po                           2 /  17 ( 11.0% translated)
    - library.po                      11 / 142 (  7.0% translated)
    - programming.po                  13 / 372 (  3.0% translated)
    - windows.po                       3 /  47 (  6.0% translated)
    ...
    

• Listing fuzzy entries

  • make fuzzy

    > make fuzzy
    for file in *.po */*.po; do echo $(msgattrib --only-fuzzy --no-obsolete "$file" | grep -c '#, fuzzy') $file; done | grep -v ^0 | sort -gr
    163 library/functions.po
    8 library/statistics.po
    5 c-api/function.po
    5 c-api/datetime.po
    4 library/unittest.po
    3 library/heapq.po
    ...
    

  • potodo --only-fuzzy

    > potodo -f
    # c-api (5.20% done)
    
    - datetime.po                      8 /  41 ( 19.0% translated), 5 fuzzy
    - dict.po                          5 /  30 ( 16.0% translated), 1 fuzzy
    - function.po                      4 /  18 ( 22.0% translated), 5 fuzzy
    - unicode.po                       5 / 334 (  1.0% translated), 1 fuzzy
    
    
    # distutils (0.00% done)
    
    - examples.po                      0 /  46 (  0.0% translated), 1 fuzzy
    
    
    # faq (9.22% done)
    
    - design.po                       13 / 141 (  9.0% translated), 2 fuzzy
    ...
    

• Get overall progress

  • make progress

    > make progress
    4.4%
    

  • potodo | tail -n2 | head -n1 | cut -c 10- | sed 's/[%].*$/%/g'

    > potodo | tail -n2 | head -n1 | cut -c 10- |  sed 's/[%].*$/%/g'
    4.31%
    

Start with the repository's Makefile commands for todo, fuzzy, and progress, then compare their output with the documented potodo examples in this issue. Check how potodo would be invoked in the Makefile and whether its output should remain a command result or be stored as a file. Done means the selected translation-status commands provide the intended potodo-style results.