Add Component Watching

[arky]

It would be good to have component watching feature on this bugzilla.

[julen]

I believe component watching is not available in Bugzilla core, and is probably an extension.

To some extent, component watching could be achieved by setting the default assignee for each component to a different email address ([email protected], [email protected]...). Then users could watch those email addresses.

Unfortunately this would only catch bugs with the default assignee.