Summary:
Protobuf based APIs are becoming more common (i.e. gRPC) but are difficult to inspect. Unlike plain text data formats (JSON), Protobuf calls transmit binary data requiring the format to be known ahead of time, making ad-hoc inspection impossible. This PR allows for those format definitions (messages in protobuf terminology) to be transmitted from the client to the network inspector plugin. These definitions are then imported into ProtobufJS which enables the binary data transmitted to be inspected as easily as JSON data.
See Retrofit PR in https://github.com/facebook/flipper/pull/2084
## Changelog
* Add ProtobufJS library to network plugin
* New `ProtobufFormatter` UI in `RequestDetails`
* `ProtobufDefinitionsRepository` to cache and load protobuf defintions
* `addProtobufDefinitions` call in the Android network plugin
Pull Request resolved: https://github.com/facebook/flipper/pull/2080
Test Plan: 
Reviewed By: mweststrate
Differential Revision: D27507451
Pulled By: passy
fbshipit-source-id: 586d891b74f2b17d28fe7a2a99074da755851f38
Summary:
Here I'm changing plugin repository structure to allow re-using of shared packages between both public and fb-internal plugins, and to ensure that public plugins has their own yarn.lock as this will be required to implement reproducible jobs checking plugin compatibility with released flipper versions.
Please note that there are a lot of moved files in this diff, make sure to click "Expand all" to see all that actually changed (there are not much of them actually).
New proposed structure for plugin packages:
```
- root
- node_modules - modules included into Flipper: flipper, flipper-plugin, react, antd, emotion
-- plugins
--- node_modules - modules used by both public and fb-internal plugins (shared libs will be linked here, see D27034936)
--- public
---- node_modules - modules used by public plugins
---- pluginA
----- node_modules - modules used by plugin A exclusively
---- pluginB
----- node_modules - modules used by plugin B exclusively
--- fb
---- node_modules - modules used by fb-internal plugins
---- pluginC
----- node_modules - modules used by plugin C exclusively
---- pluginD
----- node_modules - modules used by plugin D exclusively
```
I've moved all public plugins under dir "plugins/public" and excluded them from root yarn workspaces. Instead, they will have their own yarn workspaces config and yarn.lock and they will use flipper modules as peer dependencies.
Reviewed By: mweststrate
Differential Revision: D27034108
fbshipit-source-id: c2310e3c5bfe7526033f51b46c0ae40199fd7586
