fix #6857

Fixes #5116

The desktop frontend now treats the "name" parameter of mention as
a string to display unconditionally. But the Diaspora::Mentionable
renders mentions the different way: "name" is treated as a fallback
string which is rendered only if the person's name is unavailable.
This reflects on the mobile version ATM. This patch makes it behave
the same way as the current desktop version does.

style improvements

new line

applied changes

applied changes

all data is included in the federated status_message, so we can validate
on receive. add the photos to the status_message before save.

This was only an alias for "text", and "raw_message" is also not used
for federation anymore, so we can drop it.

Messagebus closed in 2015. See https://web.archive.org/web/20150623093956/https://www.messagebus.com/ for more information.

ignoring the error message

Previously it returned the return value of Logging::Logger#warn, which
is true for loggers that log the warn level. However
Diaspora::Federation::Receive::receive_relayable checks the return value
for truthiness in order to decide whether to attempt to relay it,
resulting in a NoMethodError: undefined method `parent' for
true:TrueClass in Diaspora::Federation::Receive::relay_relayable

This change is cosmetic as the exception raised prevented any action
that shouldn't happen anyway, so there's no actual logic change.

the check that the participation parent author is local is now done in
the diaspora_federation gem

send retraction for relayable to target author if retracted by parent author

only deliver to parent author

also refactored relayable specs to use `let`