* This introduces a new event type `realm_linkifiers` and
a new key for the initial data fetch of the same name.
Newer clients will be expected to use these.
* Backwards compatibility is ensured by changing neither
the current event nor the /register key. The data which
these hold is the same as before, but internally, it is
generated by processing the `realm_linkifiers` data.
We send both the old and the new event types to clients
whenever the linkifiers are changed.
Older clients will simply ignore the new event type, and
vice versa.
* The `realm/filters:GET` endpoint (which returns tuples)
is currently used by none of the official Zulip clients.
This commit replaces it with `realm/linkifiers:GET` which
returns data in the new dictionary format.
TODO: Update the `get_realm_filters` method in the API
bindings, to hit this new URL instead of the old one.
* This also updates the webapp frontend to use the newer
events and keys.
This is a prep change to eventually completely
replace the term "filter" with "linkifier" in
the codebase.
This only renames files. Code changes will be
done in further commits.
Abhijeet Prasad Bodas