remove old packages and scripts

package.json

@@ -7,8 +7,6 @@
         "@babel/plugin-proposal-decorators": "^7.6.0",
         "@babel/plugin-transform-react-jsx": "^7.3.0",
         "@babel/types": "^7.7.4",
-        "@ledgerhq/hw-app-eth": "^4.72.1",
-        "@ledgerhq/hw-transport-u2f": "^4.72.1",
         "@material-ui/core": "^4.5.0",
         "@material-ui/icons": "^4.4.3",
         "@material-ui/lab": "^4.0.0-alpha.28",
@@ -23,21 +21,18 @@
         "@web3-react/core": "^6.0.0-beta.19",
         "@web3-react/injected-connector": "^6.0.0-beta.25",
         "@web3-react/network-connector": "^6.0.0-beta.25",
-        "abi-decoder": "^2.2.2",
         "babel-eslint": "10.0.3",
         "babel-jest": "^24.9.0",
         "babel-loader": "8.0.6",
         "babel-plugin-named-asset-import": "^0.3.4",
         "babel-preset-react-app": "^9.0.2",
         "@balancer-labs/sor": "^0.2.2",
-        "big.js": "^5.2.2",
         "bignumber.js": "^9.0.0",
         "camelcase": "^5.2.0",
         "case-sensitive-paths-webpack-plugin": "2.2.0",
         "chart.js": "^2.9.3",
         "copy-to-clipboard": "^3.2.0",
         "css-loader": "2.1.1",
-        "decimal.js": "^10.2.0",
         "dotenv": "^8.1.0",
         "dotenv-expand": "5.1.0",
         "eslint": "^6.1.0",
@@ -48,8 +43,6 @@
         "eslint-plugin-jsx-a11y": "6.2.3",
         "eslint-plugin-react": "7.14.3",
         "eslint-plugin-react-hooks": "^1.6.1",
-        "ethereumjs-tx": "^2.1.1",
-        "ethereumjs-util": "^6.1.0",
         "ethers": "^4.0.40",
         "file-loader": "3.0.1",
         "fs-extra": "7.0.1",
@@ -66,7 +59,6 @@
         "mini-css-extract-plugin": "0.8.0",
         "mobx": "^5.14.0",
         "mobx-react": "^6.1.3",
-        "mobx-state-tree": "^3.15.0",
         "node-sass": "^4.12.0",
         "optimize-css-assets-webpack-plugin": "5.0.3",
         "pnp-webpack-plugin": "1.5.0",
@@ -97,7 +89,6 @@
         "sass-extract-loader": "^1.1.0",
         "sass-loader": "7.2.0",
         "semver": "6.3.0",
-        "strip-hex-prefix": "^1.0.0",
         "style-loader": "1.0.0",
         "styled-components": "^4.4.1",
         "terser-webpack-plugin": "1.4.1",
@@ -107,7 +98,6 @@
         "tslint-react": "^4.1.0",
         "typescript": "<3.7.0",
         "url-loader": "2.1.0",
-        "web3-provider-engine": "^15.0.3",
         "webpack": "4.41.0",
         "webpack-dev-server": "3.2.1",
         "webpack-manifest-plugin": "2.1.1",