dynlevy tracks realm size tier in variable

The character variable ````rsz_idx```` now corresponds to the dynlevy law tier set for that ruler plus 1 (so ````dynlevy0_0```` corresponds to 1).  For counts, the variable isn't guaranteed to be set in advance, but calling ````emf_dynlevy.20```` on any landed ruler is guaranteed to set it to at least 1.  ````realm_size```` can thus be approximately linearly tracked via ````rsz_idx```` in variable equations.