"Remote" realms in the TR configuration file are redundant

[Jennifer Richards]

"Remote" realms---realms for which the trust router knows only that a realm exists---were introduced to allow testing of trust route flooding before community flooding was implemented. As far as I know, there is no plausible use case for these now that community information is shared between peers. It would be a good idea to remove these. I don't think it should affect any configurations in actual use.

Correction/clarification: The remote realms are needed to allow a locally defined community to include remote realms. It would be possible to do away with the entries in the "realms" section, instead inferring the existence of remote realms when an unknown realm is listed in a "community" definition.

There is a balance to strike between ease of use and protection against problems created by typos. It is somewhat inconvenient to have to list remote realms twice, but it does avoid a single error from creating an imaginary realm and silently hiding the fact that the actual realm is not being properly included in the community.