volume-server, refactored handling of config and cmd args

src/mol-util/string.ts

src/servers/volume/config.ts

src/servers/volume/local.ts

src/servers/volume/pack.ts

src/servers/volume/server-config.ts

src/servers/volume/server.ts

src/servers/volume/server/api.ts

src/servers/volume/server/documentation.ts

src/servers/volume/server/query/execute.ts

src/servers/volume/server/web-api.ts