Add license header to all source files. Fix #1217

app/lib/db/DBHead.ts

app/lib/db/DBTransaction.ts

app/lib/dto/BlockDTO.ts

app/lib/dto/CertificationDTO.ts

app/lib/dto/Cloneable.ts

app/lib/dto/ConfDTO.ts

app/lib/dto/IdentityDTO.ts

app/lib/dto/Jsonable.ts

app/lib/dto/MembershipDTO.ts

app/lib/dto/MerkleDTO.ts

app/lib/dto/PeerDTO.ts

app/lib/dto/RevocationDTO.ts

app/lib/dto/TransactionDTO.ts

app/lib/helpers/merkle.ts

app/lib/indexer.ts

app/lib/logger.ts

app/lib/other_constants.ts

app/lib/proxy.ts

app/lib/rules/global_rules.ts

app/lib/rules/helpers.ts