Feature/add support for cosmos and polkadot (#577)

* Add support for cryptocurrencies ATOM and DOT

* Update changelog

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Added
+
+- Added support for cryptocurrencies _Cosmos_ (`ATOM-USD`) and _Polkadot_ (`DOT-USD`)
+
 ### Changed
 
 - Increased the historical data chart of the _Fear & Greed Index_ (market mood) to 30 days

apps/api/src/services/cryptocurrency/custom-cryptocurrencies.json

@@ -1,7 +1,9 @@
 {
   "1INCH": "1inch",
   "ALGO": "Algorand",
+  "ATOM": "Cosmos",
   "AVAX": "Avalanche",
+  "DOT": "Polkadot",
   "MATIC": "Polygon",
   "SHIB": "Shiba Inu",
   "SOL": "Solana",