Update requirements.txt for Compatibility and Missing Dependencies

[Abhinand-p]

I've encountered several issues while trying to set up the environment for the word-level module due to inconsistencies and missing information in the requirements.txt file.

Here are the specific problems:

1. Pytorch Version Compatibility:

The specified version Pytorch=0.4.0 requires Python 3.6. However, the package git+https://github.com/zhijing-jin/efficiency.git needs Python version >3.7.1. This creates a conflict in the required Python versions.

2. Missing Dependency:

The requirements.txt does not mention the need to clone the NeuroNLP2 repository to execute multi_runs_conll.py. This can be fixed by cloning it inside the GraphIE/word-level/examples/ directory as installation is not supported with pip and there is no setup.py support:

git clone https://github.com/XuezheMax/NeuroNLP2.git

3. Incorrect URL in requirements.txt:

The line git+git://github.com/zhijing-jin/efficiency.git should be corrected to git+https://github.com/zhijing-jin/efficiency.git.