Add community explorers

[mamirpanah]

This change is 

[alinetskyi]

Thank you for submitting this PR!
Unfortunately, we can't merge it yet, Market Cap is displayed incorrectly on your explorer.

[mamirpanah]

Hello and thanks for your feedback
we are aware that market cap can be calculated via supply * price ( and we calculate based on this in our advanced analytics https://explorer.chainroot.io/advanced-analytics/coreum/market )
but as we and many other explorers use CoinGecko as a valid source of pricing and market cap info
the market cap in CoinGecko for Coreum is unfortunately not set, as you can see from link below:
https://www.coingecko.com/en/coins/coreum
however we have changed the market cap to show "-" instead of 0 to not to convey wrong meaning.

[alinetskyi]

I can still see that market cap is "$0"
Please let me know once you've updated it and we will merge this PR.

[mamirpanah]

Thanks for your attention, we updated our explorer and advanced-analytics to show "-" instead of 0 for Coreum to not to convey wrong meaning as said above.