Support OData Edm.Stream #164

Metadata can expose some property as stream. Imagine PDF file, images or even video files. Python core 'io' module seems like good place to start, especially when working with service returning large files.

odata spec:
https://www.odata.org/blog/enhancing-odata-support-for-streams/

code reference point:

Quick fix for small files seems to be the PR #145 (sample metadata or network log was not provided, so just guessing). But when tried to write the test by myself for this PR and investigated possible usage scenario, found that the problem is bigger.