Freeciv

I send first version of patch implementing localized/translatable counters.

• To initialize a name_translation struct, use the NAME_INIT macro rather than an explicit initializer or compound literal – the internal shape of the structure is not public.
• In counters_init(), name_set should probably not happen inside the loop – that code will likely change anyway before it becomes relevant, but I'd rather avoid the possibility of accidentally giving multiple different counters the same rule_name.
• counter_by_rule_name() should use counter_rule_name(), rather than accessing the name struct directly
• In counters.h, put a /* common */ comment before the include of name_translation.h (also see the "Including Headers" section in doc/CodingStyle, or how includes are structured in other files).

Also, I just remembered: In order to be translatable, the name should be tagged with the N_() macro – that marks the string, but doesn't translate it (since we don't want to translate the rule name). Also, since the string "Owned" is used in other places, it should be qualified with something like ?counter:, so N_("?counter:Owned").