Add option to read from binary streams in ods-tools package

[sambles]

Description

From: OasisLMF/OasisPlatform#724 (comment)

I agree it'd be nice if ods_tools supported this natively.
For this PR on Platform, I approve the current implementation with io.BytesIO workaround - we'll update if/when we update the ods_tools API.

Looking at OedExposure, I see there is an OedSource.from_file_path() method that is triggered if the file is a path, but from_file_path only returns an initialised OedSource without actually reading the data from file.
Since OedSource.from_dataframe() loads the data, I think we should just have OedSource.from_file_path() to load the data before returning.
@sstruzik can we do that or perhaps open an issue on the ods repo to track this?