uncomplete, added get_P_from_mm_T. encountered what looks like a big
error in previous code -> will switch back to that and fix it to see
what happens.

nothing major

introduced new get_P function, completely re-did Vdot solution
function. Added a 6th variable (U_tg).

I was calculating rho_tg, T_tg assuming Q = 1, I switched it to use
U_tg/m_tg instead and get actual Q.

now it runs faster than using refprop

also found a minor error and fixed it in bubble_growth

new code for generating PDT_table, also started using qinterp2 to
access PDT_table (much faster than interp2).

now more things are passed from bubble_growth. note that dyer_flow
probably won’t work with other tank modeling codes now.

combined 2 pairs of calls down to 2 calls

now the code from get_P is duplicated (using PDT_table instead of
refprop)

made it so save interval is time based, not loop index based. not sure
what else I did…