The GALAH survey and Gaia DR2: dissecting the stellar disc's phase space by age, action, chemistry, and location by Bland-Hawthorn, J, Sharma, S, Tepper-Garcia, T, Binney, J, Freeman, KC, Hayden, MR, Kos, J, De Silva, GM, Ellis, S, Lewis, GF, Asplund, M, Buder, S, Casey, AR, D'Orazi, V, Duong, L, Khanna, S, Lin, J, Lind, K, Martell, SL, Ness, MK, Simpson, JD, Zucker, DB, Zwitter, T, Kafle, PR, Quillen, AC, Ting, Y-S, Wyse, RFG, Team, GALAH