Improve documentation and web page

[xmnlab]

Links:

kobo

link: kobo.epigraphhub.org

epigraphhub

link: https://github.com/thegraphnetwork/EpiGraphHub
Summary: Superset instance prepared for EpiGraphHub project

EpiGraphHubPy

link: https://github.com/thegraphnetwork/epigraphhub_py
summary: Python library used by EpiGraphHub

r-epigraphhub

link: https://github.com/thegraphnetwork/r-epigraphhub
summary R library used by EpiGraphHub

epigraphhub-lib-docs

link: https://github.com/thegraphnetwork/epigraphhub-lib-docs
summary: central place for epigraphhub library documentation (python and r)

epigraphhub-enhancement-proposals

link: https://github.com/thegraphnetwork/epigraphhub-enhancement-proposals
summary: place to discuss enhancements that has big impact to the EpiGraphHub ecosystem

[xmnlab]

cc @Anavelyz @YurelyCamacho