Add an --stdin option to read content from stdin

[dagwieers]

Someone request to be able to pipe a document to standard input for doing conversions. Much like the --stdout option, we could implement an ---stdin option.

[jorangreef]

This would be a great help.

[dagwieers]

I accept contributions ;-)

[hyper-space]

I second the motion. I'd do it myself by I'm a total hack at python and this one is over my head. Great job by the way!

[pataquets]

There are 2 different PR with proposals for stdin. I'm +1 on this feature.
@dagwieers: Could you please provide feedback to allow further progress? Thus, interested people can focus on improving and testing. TIA.

[dagwieers]

Yes, this one can be closed. Seems to work very well, I am pleased !

[TobiasJu]

Hey guys can you short explain how to use --stdin?
Because, when using stdin to pass a string for writing into a pdf, i get this error msg.:
unoconv -f pdf --output test.pdf --stdin <<< "This is a test."

Expected bytes object or ByteSequence, got <class 'str'> instead.