Replace outdated references to github.com/Ericsson/eiffel

[magnusbaeck]

Description

There are about a handful of references to https://github.com/Ericsson/eiffel in the documentation. This isn't disastrous since that URL redirects to https://github.com/eiffel-community/eiffel but it's nevertheless incorrect.

Motivation

There's no reason to link to outdated URLs, even if they (currently) redirect to the current location.

Exemplification

N/A

Benefits

Decreased risk of spreading outdated URLs.

Possible Drawbacks

None.