Adding loader for Extreme Metal Vocals Dataset (EMVD)

[dsuedholt]

Description

Please include the following information at the top level docstring for the dataset's module mydataset.py:

• Describe annotations included in the dataset
• Indicate the size of the datasets (e.g. number files and duration, hours)
• Mention the origin of the dataset (e.g. creator, institution)
• Describe the type of music included in the dataset
• Indicate any relevant papers related to the dataset
• Include a description about how the data can be accessed and the license it uses (if applicable)

Dataset loaders checklist:

• Create a script in scripts/, e.g. make_my_dataset_index.py, which generates an index file.
• Run the script on the canonical version of the dataset and upload the index to Zenodo Audio Data Loaders community.
• Create a sample version of the index with the necessary information for testing.
• Create a module in mirdata, e.g. mirdata/my_dataset.py
• Create tests for your loader in tests/datasets/, e.g. test_my_dataset.py
• Add your module to docs/source/mirdata.rst and docs/source/table.rst
• Run black, flake8 and mypy (see Running your tests locally).
• Run tests/test_full_dataset.py on your dataset.
• Check that codecov coverage does not decrease.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.10%. Comparing base (581f4c4) to head (541edfa).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #650      +/-   ##
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+ Coverage   97.07%   97.10%   +0.03%     
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  Files          68       69       +1     
  Lines        7583     7674      +91     
==========================================
+ Hits         7361     7452      +91     
  Misses        222      222