Fit global epistasis models

• Lib-1_2022-03-25_thaw-1_VSVG_control_1_vs_2022-04-13_thaw-1_no-antibody_control_1

• Lib-1_2022-03-25_thaw-1_VSVG_control_2_vs_2022-04-13_thaw-1_no-antibody_control_2

• Lib-2_2022-06-22_thaw-1_VSVG_control_1_vs_2022-06-22_thaw-1_no-antibody_control_1

• Lib-3_2022-06-22_thaw-1_VSVG_control_1_vs_2022-06-22_thaw-1_no-antibody_control_1