Client implementation + Flipper fixes

[sugarmanz]

New packages:

• client
• flipper-plugin
• utils

Reworked:

• content organization — each plugin should also have a content package that builds the devtools plugin content and exports as plugin data
• core plugin methods for reducing overhead on data dispatching
• configurable style overlay for basic plugin (ios not supported yet)

[spentacular]

Go to bed

[sugarmanz]

/canary