Merge branch 'master' into gl-lines

# Conflicts:
#	src/mol-geo/geometry/geometry.ts
#	src/mol-geo/geometry/lines/lines.ts
#	src/mol-geo/geometry/points/points.ts
#	src/mol-repr/structure/representation/cartoon.ts
#	src/mol-repr/structure/visual/inter-unit-link-cylinder.ts
#	src/mol-repr/structure/visual/polymer-backbone-cylinder.ts
#	src/mol-repr/structure/visual/polymer-direction-wedge.ts
#	src/mol-repr/structure/visual/polymer-gap-cylinder.ts
#	src/mol-repr/structure/visual/polymer-trace-mesh.ts
#	src/mol-repr/structure/visual/util/link.ts
#	src/mol-repr/volume/index.ts