facebook/metro v0.55.0 on GitHub

[Breaking]: Introduce Fast Refresh as a replacement for hot reloading (https://twitter.com/reactnative/status/1144629612921720833)
[Breaking]: Remove providesModuleNodeModules option (7b46150).
[New package]: ob1, a small library for working with 0- and 1-based offsets in a type-checked way (437374f).
[Feature]: Include original and inferred function names in source maps (64fc81e, 4bb9969).
[Feature]: New source map consumer implementation (ccd508c) and source map composition function (6017085) in metro-source-map.
[Feature]: Expose a modulesOnly option for the bundle endpoint (79904d8).
[Fixes]: Several bugfixes in Metro server (39892a2, affd060, 721cbe2, dc2f29f, 118f1f8, etc).
[Fixes]: Support import {default as localName} (2f15a05).
[Fixes]: Make Metro server more responsive during a symbolication request (99cd176).
[Experimental]: Add an "Import Bundle" mode to Metro (9dd961a).