Make ITK keywords in PyPI consistent

### Description

ITK-related keywords across PyPI packages (e.g. remotes, etc.) are not consistent: some use uppercase (`ITK`), some lowercase (`itk`), some have `InsightToolkit` from pre-cookiecutter days, etc.

Also, some short descriptions:
- End with a period, others do not, etc.
- Start with a seemingly unnecessary `An ITK remote module (...)`, etc.

### Expected information

Make:
- All keywords consistent.
- All descriptions consistent and accurate.

### Actual information

ITK-related packages in PyPI have inconsistent keywords and descriptions.

### Versions

N/A.

### Additional Information

None.