Consolidate exporter-endpoints

[yearn-linear-gh-sync]

Currently we have our code for the various api endpoints in multiple repos:

• /v1 routes: https://github.com/yearn/yearn-exporter/blob/master/yearn/api.py
• apybot(kx9x): https://yearnapybot.azurewebsites.net/api/chains/250/vaults/0x0DEC85e74A92c52b7F708c4B10207D9560CEFaf0/pps/1d
• yearn-exporter-api (not published yet): https://github.com/mariuspod/yearn-exporter-api

This has the following drawbacks:

• request sending/parsing is duplicated, possibly in different programming languages
• portability is weak

Therefore we should merge this into a single repo, possibly yearn-exporter as it's the closest to the data and we have already the /v1 routes in it.

[0xkofee]

@mariuspod Is this related to https://github.com/yearn/yearn-watch/pull/229 ? Seems like there is a big refactor to use the SDK for calls... just letting you know