WIP: Refactoring dnsfoam
Summary
dnsFoam is refactored, and its external behaviour is verified through dnsFoam/boxTurb16 tutorial.
diff all the fields of {enstrophy,graphs,p,phi,U} from the original tutorial, and refactored dnsfoam yielded no change.
Resolved bugs (If applicable)
N/A
Details of new models (If applicable)
N/A
Risks
N/A