Update solidity to 0.8.0.

Author: MoMannn

.solhint.json

@@ -1,9 +1,6 @@
 {
   "extends": "solhint:default",
   "rules": {
-    "indent": ["error", 2],
-    "bracket-align": "off",
-    "two-lines-top-level-separator": "off",
-    "max-line-length": 100
+    "max-line-length": ["warn", 100]
   }
 }

README.md

@@ -77,7 +77,7 @@ You have created and have possession of unique glass-blown artwork (each having
 To do this, simply paste the code below into Remix and deploy the smart contract. You will "mint" a token for each new piece of artwork you want to see. Then you will "burn" that token when you surrender physical possession of the piece.
 
 ```solidity
-pragma solidity 0.6.2;
+pragma solidity 0.8.0;
 
 import "https://github.com/0xcert/ethereum-erc721/src/contracts/tokens/nf-token-metadata.sol";
 import "https://github.com/0xcert/ethereum-erc721/src/contracts/ownership/ownable.sol";

package-lock.json

@@ -72,8 +72,8 @@
     "@specron/flattener": "0.15.1",
     "@specron/spec": "0.15.1",
     "@types/node": "13.7.0",
-    "solc": "0.6.2",
-    "solhint": "2.3.0",
+    "solc": "0.8.0",
+    "solhint": "3.3.2",
     "ts-node": "8.6.2",
     "typescript": "3.7.5",
     "web3": "1.2.5-rc.0"