Rest framework (#24)

* Add rest framework for API: First Commit

* modify some shell scripts to make variable references safer; modify some python scripts to reduce the code complexity and cyclomatic complexity of functions.

* Add REST API for some webvirtcloud functions. Instance list/delete/create, compute list/delete/create, storages-network list/retrieve. Add swagger and redoc for API interface

* update requirements

Co-authored-by: herengui <herengui@uniontech.com>

instances/migrations/0010_auto_20220722_0812.py

@@ -0,0 +1,22 @@
+# Generated by Django 3.2.14 on 2022-07-22 08:12
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('instances', '0009_auto_20200717_0524'),
+    ]
+
+    operations = [
+        migrations.AlterModelOptions(
+            name='permissionset',
+            options={'default_permissions': (), 'managed': False, 'permissions': [('clone_instances', 'Can clone instances'), ('passwordless_console', 'Can access console without password'), ('view_instances', 'Can view instances'), ('snapshot_instances', 'Can snapshot instances')]},
+        ),
+        migrations.AddField(
+            model_name='instance',
+            name='drbd',
+            field=models.CharField(default='None', max_length=24, verbose_name='drbd'),
+        ),
+    ]