Refactored project structure

src/common/_spec/collections.spec.ts

src/common/collections/chunked-array.ts

src/common/collections/hash-functions.ts

src/common/collections/hash-set.ts

src/common/collections/int-tuple.ts

src/common/collections/iterator.ts

src/common/collections/linked-index.ts

src/common/collections/ordered-set.ts

src/common/collections/sort.ts

src/common/computation.ts

src/common/math/linear-algebra.ts

src/common/scheduler.ts

src/index.d.ts

src/mol-data/_spec/atom-set.spec.ts

src/mol-data/atom-set.ts

src/mol-data/structure/data.ts

src/mol-data/structure/model.ts

src/mol-data/structure/selectors.ts

src/mol-data/structure/selectors/common.ts

src/mol-data/structure/selectors/mmcif.ts