[FIX+IMP] l10n_es_aeat_sii: Better tax dict treatment + PEPP8
[FIX+IMP] l10n_es_aeat_sii: Better tax dict treatment + PEPP8

algiopensource/l10n-spain,JuanjoA/l10n-spain,syci/l10n-spain,Comunitea/l10n-spain,diagramsoftware/l10n-spain,algiopensource/l10n-spain,agaldona/l10n-spain,Comunitea/l10n-spain,diagramsoftware/l10n-spain,agaldona/l10n-spain,JuanjoA/l10n-spain,syci/l10n-spain,Comunitea/l10n-spain