feat(contracts): removing unnecesary dependencies

feat(contracts): rename sha3 method, apply recommend suggestions from code review

feat(contracts): FDSRegistry is ENSRegistry, supports @ensdomains interface. fix prettier issues. removed subdomain

contracts/FDSRegistrar.sol

@@ -8,12 +8,17 @@ import "@ensdomains/ens-contracts/contracts/ethregistrar/BaseRegistrarImplementa
  * The ENS registry contract.
  */
 contract FDSRegistrar is BaseRegistrarImplementation {
-  bytes32 constant NAME_HASH = 0x854683790d7d8c6e4d741a8a5f01dc2952c51f38407545ea5117889dc81bd141;
+  bytes32 constant ZERO_HASH = 0x0000000000000000000000000000000000000000000000000000000000000000;
+
+  // from specification https://eips.ethereum.org/EIPS/eip-137
+  bytes32 constant NAME_HASH = keccak256(abi.encodePacked(ZERO_HASH, keccak256(abi.encodePacked("fds"))));
+  // 0x854683790d7d8c6e4d741a8a5f01dc2952c51f38407545ea5117889dc81bd141;
+
   /**
    * @dev Constructs a new ENS registrar.
    */
   constructor(ENS _registry) 
-  BaseRegistrarImplementation(_registry, NAME_HASH) {
+    BaseRegistrarImplementation(_registry, NAME_HASH) {
   }
 
 

contracts/FDSRegistry.sol

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import "@ensdomains/ens-contracts/contracts/registry/ENSRegistry.sol";
+
+/**
+ * The FDS registry contract.
+ */
+contract FDSRegistry is ENSRegistry {
+
+  /**
+   * @dev Constructs a new registry
+   */
+  constructor() 
+    ENSRegistry() {
+  }
+}

contracts/PublicResolver.sol

@@ -1,7 +1,8 @@
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.0;
 
-import "./ENS.sol";
+import "@ensdomains/ens-contracts/contracts/registry/ENS.sol";
+
 
 /**
  * A simple resolver anyone can use; only allows the owner of a node to set its