feat: remove unused gsn contracts (#126)

* feat: remove unused gsn contracts

* refactor: gsn related functions

Author: superical

contracts/GsnCapable.sol

@@ -2,8 +2,6 @@ export const DOCUMENT_STORE_CREATOR_ROPSTEN = "0x4077534e82C97Be03A07FB10f5c853d
 export const DOCUMENT_STORE_CREATOR_MAINNET = "0x0";
 export const PROXY_FACTORY_ROPSTEN = "0xba2501bf20593f156879c17d38b6c245ca65de80";
 export const PROXY_FACTORY_MAINNET = "0x0";
-export const TRUST_FORWARDER_ROPSTEN = "0x25CEd1955423BA34332Ec1B60154967750a0297D";
-export const TRUST_FORWARDER_MAINNET = "0xa530F85085C6FE2f866E7FdB716849714a89f4CD";
 
 export const getDocumentStoreCreatorAddress = (networkId?: number) => {
   if (networkId === 3) return DOCUMENT_STORE_CREATOR_ROPSTEN;
@@ -14,8 +12,3 @@ export const getProxyFactoryAddress = (networkId?: number) => {
   if (networkId === 3) return PROXY_FACTORY_ROPSTEN;
   return PROXY_FACTORY_MAINNET;
 };
-
-export const getTrustForwarderAddress = (networkId?: number) => {
-  if (networkId === 3) return TRUST_FORWARDER_ROPSTEN;
-  return TRUST_FORWARDER_MAINNET;
-};