Add the atob & btoa npm module definitions (#25416)

* feat(types): add the atob btoa npm module definitions

* style(lint): shorten typescript version

* chore(tslint): remove unnecessary rules

* chore(tslint): fix linting errors

types/atob/atob-tests.ts

@@ -0,0 +1,3 @@
+import atob from 'atob';
+
+atob('foo');

types/atob/index.d.ts

@@ -0,0 +1,7 @@
+// Type definitions for atob 2.1
+// Project: https://git.coolaj86.com/coolaj86/atob.js.git
+// Definitions by: John Wright <https://github.com/johngeorgewright>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+// TypeScript Version: 2.8
+
+export default function(str: string): string;

types/atob/tsconfig.json

@@ -0,0 +1,21 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "strictFunctionTypes": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "lib": ["es6"],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "atob-tests.ts"
+    ]
+}

types/atob/tslint.json

@@ -0,0 +1,3 @@
+{
+    "extends": "dtslint/dt.json"
+}

types/btoa/btoa-tests.ts

@@ -0,0 +1,3 @@
+import btoa from 'btoa';
+
+btoa('foo');

types/btoa/index.d.ts

@@ -0,0 +1,7 @@
+// Type definitions for btoa 1.2
+// Project: https://git.coolaj86.com/coolaj86/btoa.js
+// Definitions by: John Wright <https://github.com/johngeorgewright>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+// TypeScript Version: 2.8
+
+export default function(str: string): string;

types/btoa/tsconfig.json

@@ -0,0 +1,21 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "strictFunctionTypes": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "lib": ["es6"],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "btoa-tests.ts"
+    ]
+}

types/btoa/tslint.json

@@ -0,0 +1,3 @@
+{
+    "extends": "dtslint/dt.json"
+}