Documentation URL(s) with the issue:
https://github.com/tensorflow/models/blob/master/research/object_detection/g3doc/installation.md

Description of the issue (what needs to be changed):
As objection detection module has NOT yet support any Tensorflow v2 versions, current description is misleading, there are a few issues opened every month due to this, please clarify it in the installation guide.

1. "Tensorflow (>=1.12.0)" should be updated as "Tensorflow (>=1.12.0 and < 2.0), support for v2 will be after "

2. The instruction "pip install tensorflow" will install TF v2, which will break everything, should be updated as "pip install tensorflow==1.15"