clean up memory
Merge branch 'fluidity-core/MultiFluids_Dev' of github.com:jrper/MultiFluidFluidity into fluidity-core/MultiFluids_Dev

Conflicts:
	legacy_reservoir_prototype/src/cv-adv-dif.F90
Merge branch 'fluidity-core/MultiFluids_Dev' of github.com:jrper/MultiFluidFluidity into fluidity-core/MultiFluids_Dev