Regio- and Stereoselective 1,3-dipolar Cycloaddition of Azomethine Ylides Based on Isatins and (thia)proline to 3-nitro-2-(trifluoro(trichloro)methyl)-2H-chromenes: Synthesis and Cytotoxic Activity of 6-(trihalomethyl)-spiro[chromeno(thia)pyrrolizidine-11,3'-indolin]-2'-ones