Proxy the various external API that the client uses

[rdig]

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| DRAFT                                                                                      |
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Done:

• Segment

Todo:

• Pinata
• Coingeko

Will not be done now:

• bscscan
• etherscan

Proxy Endpoint Wildcard	Description
/ui-events/v1/projects/*	Get the specific Segment project init settings using the write key
/ui-events/v1/*	Called when sending the specific event types

Contributes to #10

[rdig]

Closing due to the same reason as here JoinColony/colonyCDapp#1899 (comment)