add test coverage for prepost.Simulations.ManTurb64

wetb/prepost/tests/data/demo_dlc/ref/demo_dlc_remote.zip

...prepost/tests/data/demo_dlc/ref/htc/DLCs/dlc01_demos.xlsx

...s/data/demo_dlc/ref/htc/_master/demo_dlc_master_A0001.htc

.../demo_dlc/ref/htc/dlc01_demos/dlc01_steady_wsp10_s100.htc

...demo_dlc/ref/htc/dlc01_demos/dlc01_steady_wsp8_noturb.htc

...demo_dlc/ref/htc/dlc01_demos/dlc01_steady_wsp9_noturb.htc

...demo_dlc/ref/pbs_in/dlc01_demos/dlc01_steady_wsp10_s100.p

...st/tests/data/demo_dlc/ref/pbs_in/turb/turb_s100_10ms.pbs

wetb/prepost/tests/data/demo_dlc/ref/prepost/remote_tags.txt

wetb/prepost/tests/data/demo_dlc/source/demo_dlc_remote.zip

...post/tests/data/demo_dlc/source/htc/DLCs/dlc01_demos.xlsx

...ata/demo_dlc/source/htc/_master/demo_dlc_master_A0001.htc

wetb/prepost/tests/test_Simulations.py