[libtesseract] output of get_available_builders() is incomplete

[wwqgtxx]

I see the code of
https://github.com/openpaperwork/pyocr/blob/master/src/pyocr/libtesseract/tesseract_raw.py#L381
https://github.com/openpaperwork/pyocr/blob/master/src/pyocr/libtesseract/__init__.py#L110
It's showed the libtesseract was supported the numeric mode，but why in get_available_builders not allow us use DigitBuilder？

[jflesch]

Quite frankly, I totally forgot get_available_builders even existed (it's not even documented in the README). What they currently return is probably obsolete.
You can safely use DigitBuilder with libtesseract.

I'll update get_available_builders for the next release.

[jflesch]

Ok, the next next release... sorry .. :/