[Feature] 添加功能 RemoteApp (#2706)

* [Feature] RemoteApp添加Model

* [Feature] RemoteApp添加ViewSet API

* [Feature] RemoteApp添加获取connection-info API

* [Feature] Perms模块修改目录结构

* [Feature] RemoteAppPermission添加Model

* [Feature] RemoteAppPermission添加ViewSet API

* [Feature] RemoteAppPermission添加用户/用户组获取被授权的RemoteApp API

* [Feature] RemoteAppPermission添加校验用户对RemoteApp的权限 API

* [Feature] RemoteAppPermission添加获取用户授权的RemoteApp树 API

* [Feature] RemoteAppPermission添加<添加/移除>所授权的<用户/RemoteApp> API

* [Feature] RemoteApp添加创建、更新、详情、删除、用户RemoteApp等页面

* [Feature] RemoteAppPermission添加创建、更新、详情、删除、授权用户、授权RemoteApp等页面

* [Feature] RemoteApp从assets模块迁移到新添加的applications模块

* [Feature] RemoteApp/RemoteAppPermission添加迁移文件

* [Feature] RemoteApp/RemoteAppPermission修改小细节

* [Feature] RemoteApp/RemoteAppPermission修改小细节2

* [Feature] RemoteApp/RemoteAppPermission修改小细节3

* [Feature] RemoteApp更新迁移文件

* [Feature] RemoteApp/RemoteAppPermission添加翻译信息

* [Feature] RemoteApp/RemoteAppPermission删除迁移文件

* [Feature] RemoteApp/RemoteAppPermission添加迁移文件

* [Feature] RemoteApp/RemoteAppPermission修改代码风格

apps/perms/forms/remote_app_permission.py

@@ -0,0 +1,49 @@
+#  coding: utf-8
+#
+
+from django.utils.translation import ugettext as _
+from django import forms
+from orgs.mixins import OrgModelForm
+from orgs.utils import current_org
+
+from ..models import RemoteAppPermission
+
+
+__all__ = [
+    'RemoteAppPermissionCreateUpdateForm',
+]
+
+
+class RemoteAppPermissionCreateUpdateForm(OrgModelForm):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        users_field = self.fields.get('users')
+        if hasattr(users_field, 'queryset'):
+            users_field.queryset = current_org.get_org_users()
+
+    class Meta:
+        model = RemoteAppPermission
+        exclude = (
+            'id', 'date_created', 'created_by', 'org_id'
+        )
+        widgets = {
+            'users': forms.SelectMultiple(
+                attrs={'class': 'select2', 'data-placeholder': _('User')}
+            ),
+            'user_groups': forms.SelectMultiple(
+                attrs={'class': 'select2', 'data-placeholder': _('User group')}
+            ),
+            'remote_apps': forms.SelectMultiple(
+                attrs={'class': 'select2', 'data-placeholder': _('RemoteApp')}
+            )
+        }
+
+    def clean_user_groups(self):
+        users = self.cleaned_data.get('users')
+        user_groups = self.cleaned_data.get('user_groups')
+
+        if not users and not user_groups:
+            raise forms.ValidationError(
+                _("User or group at least one required")
+            )
+        return self.cleaned_data['user_groups']