Changeset 5b52a48 for protocols/msn/ns.c

Implemented per-account nick lists instead of per-protocol nick lists.
nick_t is dead, instead nicks are just saves in a per-account_t GLib
hash table. While doing this, the import_buddies command finally died
and text_save() disappeared, because the old file format can't handle
most of the new features in this branch anyway.

Still have to implement support for the new nick lists in text_load()!