Replace example domains to use example.com

[netweb]

Currently there are numerous links/examples/help URL's throughout BuddyPress using domain.com as an example.

These domains should be switched to example.com per ​http://www.iana.org/domains/reserved

Primarily domain.com links to an "ad farm" whereas ​http://example.com does not, it links to the IANA link above.

[johnjamesjacoby]

This is an easy string replacement in 13 locations, and stops us linking to an unsavory site.

Fix incoming.

[johnjamesjacoby]

In 9428:

Replace domain.com references with example.com to avoid linking to unaffiliated . Props netweb. Fixes #6183.

[netweb]

Yay :) FYI: ​http://example.org, ​http://example.net/, ​http://example.edu are also valid IANA example domains, they also have a valid wildcard SSL certificate for the 4 domains ​https://example.com