Description of Persicirhabdus sediminis gen. nov., sp nov., Roseibacillus ishigakijimensis gen. nov., sp nov., Roseibacillus ponti sp nov., Roseibacillus persicicus sp nov., Luteolibacter pohnpeiensis gen. nov., sp nov and Luteolibacter algae sp nov., six marine members of the phylum 'Verrucomicrobia', and emended descriptions of the class Verrucomicrobiae, the order Verrucomicrobiales and the family Verrucomicrobiaceae