Bug#657195: Client package descriptions unclear, multiple clients cause confusion

[Jon Dowland]

I think this could also be improved by removing the virtual package
'freeciv' (which has no reverse dependencies, lacks a description in
package managers by virtue of being a virtual package and is not in
the canonical list of virtual packages anyway[1], so seems to serve
no useful purpose) and replacing it with a metapackage which has a 
useful description and appropriate *dependencies* to install a usable
game. (That is, depends on server, not recommends.)  Then, the onus
would not necessarily be on the various client packages to explain
the whole situation themselves.

[1] http://www.debian.org/doc/packaging-manuals/virtual-package-names-list.txt