style(book-edit): add bootstrap styles

Author: robinboehm

src/app/book/book-edit/book-edit.component.html

@@ -1,12 +1,23 @@
 <h2>Edit</h2>
 <div *ngIf="book">
   <form #form="ngForm" (ngSubmit)="onSubmit(form.value)">
-    <input type="text" name="isbn" #isbn="ngModel" [(ngModel)]="book.isbn" required/><br />
-    <span [hidden]="!isbn.errors?.required">ISBN is required</span><br />
-    <input type="text" name="title" #title="ngModel" [(ngModel)]="book.title" required/><br />
-    <span [hidden]="!title.errors?.required">Title is required</span><br />
-    <input type="text" name="author" #author="ngModel" [(ngModel)]="book.author" required/><br />
-    <span [hidden]="!author.errors?.required">Author is required</span><br />
-    <button [disabled]="!form.valid" type="submit">Save</button>
+      <div class="form-group row">
+          <label for="isbn" class="col-sm-2 col-form-label">ISBN</label>
+          <input class="form-control col-sm-10" type="text" name="isbn" #isbn="ngModel" [(ngModel)]="book.isbn" readonly/>
+      </div>
+    <div class="form-group row">
+        <label for="title" class="col-sm-2 col-form-label">Title</label>
+        <input type="text" name="title" #title="ngModel" [(ngModel)]="book.title" required class="form-control col-sm-10"/>
+        <small class="col-sm-10 offset-sm-2" [hidden]="!title.errors?.required">Title is required</small>
+    </div>
+    <div class="form-group row">
+        <label for="author" class="col-sm-2 col-form-label">Author</label>
+        <input class="form-control col-sm-10" type="text" name="author" #author="ngModel" [(ngModel)]="book.author" required/>
+        <small class="col-sm-10 offset-sm-2" [hidden]="!author.errors?.required">Author is required</small>
+    </div>
+    <div class="row">
+        <button [disabled]="!form.valid" type="submit" class="btn btn-success offset-sm-2">Save</button>
+        <button [routerLink]="['/books', book.isbn]" class="btn btn-warning">Cancel</button>
+    </div>
   </form>
 </div>