Add manifest support

[naman108]

• [x] move registration to digitalpy
• [x] add manifest retrieval method to facade
• [x] add manifest name and version validation
• [x] add manifest id validation
• [x] add component in-memory persistence to prevent duplicates
• [ ] add support to pull components from PyPI if repo is in the manifest

[naman108]

pulling components from pypi can probably be done using pip install --target [componentdir] componentname