Download and Upload using IO stream

[iLLiCiTiT]

Description

Added option to download file to BytesIO and upload file from BytesIO.

Additional information

Sometimes it might be handy to be able to download content from server without storing it to a file but only to memory, or upload file from memory.

[BigRoy]

Side note is that ayon-python-api on pypi seems listed as Python 2 and Python 3 even though this change technically makes it Python 3.2+ compatible.

[iLLiCiTiT]

Side note is that ayon-python-api on pypi seems listed as Python 2 and Python 3 even though this change technically makes it Python 3.2+ compatible.

Good point will do PR changing it.

EDITED:
PR #156

[kalisp]

Code looks good, but I didn't know how to test it.
I wanted to mock downloading dependency package to BytesIO and then saving it:

but it failed:

Maybe its just my messed up test.

[kalisp]

Last commit solved my issue. Checked upload_file_from_stream seems that is not suffering from same issue.