Bump solc

packages/concordia-contracts/.solhint.json

@@ -1,7 +1,7 @@
 {
   "extends": "solhint:recommended",
   "rules": {
-    "compiler-version": ["error","^0.7.5"],
+    "compiler-version": ["error","~0.8.0"],
     "func-visibility": ["warn",{"ignoreConstructors" : true}],
     "not-rely-on-time": "off",
     "state-visibility": "off"

packages/concordia-contracts/contracts/Forum.sol

@@ -1,6 +1,5 @@
 //SPDX-License-Identifier: MIT
-pragma solidity 0.7.5;
+pragma solidity 0.8.0;
-pragma experimental ABIEncoderV2;
 
 contract Forum {
     // Error messages for require()

packages/concordia-contracts/contracts/Migrations.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: MIT
-pragma solidity 0.7.5;
+pragma solidity 0.8.0;
 
 contract Migrations {
     address public owner;

packages/concordia-contracts/contracts/PostVoting.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: MIT
-pragma solidity 0.7.5;
+pragma solidity 0.8.0;
 
 import "./Forum.sol";
 

packages/concordia-contracts/contracts/Voting.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: MIT
-pragma solidity 0.7.5;
+pragma solidity 0.8.0;
 
 import "./Forum.sol";
 

packages/concordia-contracts/test/TestVoting.sol

@@ -1,5 +1,5 @@
 //SPDX-License-Identifier: MIT
-pragma solidity 0.7.5;
+pragma solidity 0.8.0;
 
 import "truffle/Assert.sol";
 import "truffle/DeployedAddresses.sol";

packages/concordia-contracts/truffle-config.js

@@ -10,7 +10,7 @@ module.exports = {
   // to customize your Truffle configuration!
   compilers: {
     solc: {
-      version: '0.7.5',
+      version: '0.8.0',
     },
   },
   contracts_build_directory: path.join(__dirname, 'build/'),