refactoring

src/mol-base/collections/integer/impl/ordered-set.ts

src/mol-base/collections/integer/impl/sorted-array.ts

src/mol-base/collections/integer/sorted-array.ts

src/mol-base/collections/iterator.ts

src/mol-base/utils/bit-flags.ts

src/mol-data/model/properties/conformation.ts

src/mol-data/structure.ts

src/mol-data/structure/atom-set.ts

src/mol-data/structure/atom-set/properties.ts

src/mol-data/structure/atom.ts

src/mol-data/structure/base.ts

src/mol-data/structure/property.ts

src/perf-tests/structure.ts