Added ESlint linter

Author: Sapython

.eslintrc.json

@@ -0,0 +1,50 @@
+{
+  "root": true,
+  "ignorePatterns": [
+    "projects/**/*"
+  ],
+  "overrides": [
+    {
+      "files": [
+        "*.ts"
+      ],
+      "parserOptions": {
+        "project": [
+          "tsconfig.json"
+        ],
+        "createDefaultProgram": true
+      },
+      "extends": [
+        "plugin:@angular-eslint/recommended",
+        "plugin:@angular-eslint/template/process-inline-templates"
+      ],
+      "rules": {
+        "@angular-eslint/directive-selector": [
+          "error",
+          {
+            "type": "attribute",
+            "prefix": "app",
+            "style": "camelCase"
+          }
+        ],
+        "@angular-eslint/component-selector": [
+          "error",
+          {
+            "type": "element",
+            "prefix": "app",
+            "style": "kebab-case"
+          }
+        ]
+      }
+    },
+    {
+      "files": [
+        "*.html"
+      ],
+      "extends": [
+        "plugin:@angular-eslint/template/recommended"
+      ],
+      "rules": {}
+    }
+  ]
+}

angular.json

@@ -129,9 +129,21 @@
             "firebaseProject": "sapython-f016a",
             "firebaseHostingSite": "sapython-f016a"
           }
+        },
+        "lint": {
+          "builder": "@angular-eslint/builder:lint",
+          "options": {
+            "lintFilePatterns": [
+              "src/**/*.ts",
+              "src/**/*.html"
+            ]
+          }
         }
       }
     }
   },
-  "defaultProject": "SapythonBlog"
-}
+  "defaultProject": "SapythonBlog",
+  "cli": {
+    "defaultCollection": "@angular-eslint/schematics"
+  }
+}