Split pyaerocom into seperate projects

[dulte]

We need to use a scalpel to separate each part into it's own projects. It will make development, maintenance, documentation and use easier. Suggested parts should be

1. pyaerocom: colocation, statistics, basic readers
2. External readers
3. Plotting: moved to unmaintained project
4. pyAeroval: calculation of json files needed by web page

[github-actions[bot]]

This issue is stale because it has been open for 365 days with no activity. This issue will be closed in 14 days if no action is taken.

[lewisblake]

This is still relevant, and probably should become a GitHub Project.

[github-actions[bot]]

This issue is stale because it has been open for 365 days with no activity. This issue will be closed in 14 days if no action is taken.

[github-actions[bot]]

This issue was closed because it has been inactive for 14 days since being marked as stale.