Fix h0_h1 issues

[keaven]

h0_info and h1_info options give same sample size in gs_design_ahr. This is probably an issue in gs_power_npe. spec should be updated to clarify when info0 and info1 should be available. Distinction between info and info1 should be clarified in help file. Should gs_power_npe and gs_design_npe help files be combined?