Update liquid engines for 1.12.2 (Swivel and Reliant)

[RojinBaka]

Update for 1.12.2 (which renamed LVT30 and LVT45 from liquidEngine and liquidEngine2 to liquidEngine_v2 and liquidEngine2_v2 respectively):

• obsoletes v1 versions
• places v2 versions into correct tech level (HeavyRocketry)
• updates definitions for LVT05 and LVT10 to use v2 versions as templates