Synthesis and characterization of new addition compounds of bis(substituted-salicylaldehydo) cobalt(II) with 2,2′-bipyridine (bipy). Crystal and molecular structures of [CoII(3-methoxy-salicylaldehyde)2(bipy)] · CH3OH (1) and [CoII(bipy)3]Br2 · 0.5(5-chloro-salicylaldehydeH) · 1.5CH3OH (5)