Fix compilation and remove nphysics mentions #45

Job	Run time
check-fmt	5s
all-features-native (salva2d)	6m 1s
build-wasm (salva2d)	57s
all-features-native (salva3d)	6m 48s
build-native (salva2d, default)	28s
build-wasm (salva3d)	54s
examples-native (examples2d, default)	7m 39s
build-native (salva2d, parallel)	37s
examples-native (examples2d, parallel)	7m 44s
build-native (salva2d, sampling)	55s
test-native (salva2d)	31s
examples-native (examples3d, default)	7m 48s
build-native (salva2d, parry)	48s
test-native (salva3d)	35s
examples-native (examples3d, parallel)	7m 53s
build-native (salva2d, rapier)	54s
build-native (salva2d, rapier-testbed)	6m 15s
build-native (salva3d, default)	31s
build-native (salva3d, parallel)	32s
build-native (salva3d, sampling)	53s
build-native (salva3d, parry)	42s
build-native (salva3d, rapier)	59s
build-native (salva3d, rapier-testbed)	6m 5s
	1h 6m 34s

Provide feedback