## Bug description

<img width="704" alt="Screenshot 2020-11-03 at 15 59 49" src="https://user-images.githubusercontent.com/47497682/98009740-cdac2e00-1ded-11eb-940f-70cdfbbbca74.png">



The UX here is unclear - the message 'integration disabled' in the webhook URL makes me feel like maybe either either need to enter the URL and it'll work *or* maybe i"ll go to the trouble of entering the URL then it won't work because it's disabled globally.

If it is disabled globally, then this input should only appear for admin users (with perhaps a 'Request integration' button that messages the admin user as a second step)

If it just needs a webhook URL to be entered, then we should clarify this placeholder text.

Sidenote: We should add Discord since this also works [as I think the API is the same?](https://github.com/PostHog/posthog.com/issues/564)

posthog/api/user.py
import functools
import json
import os
import secrets
import urllib.parse
from typing import Optional, cast
import posthoganalytics
import requests
from django.conf import settings
from django.contrib.auth import update_session_auth_hash
from django.contrib.auth.password_validation import validate_password
from django.core.exceptions import ObjectDoesNotExist, ValidationError
from django.http import HttpResponse, JsonResponse
from django.shortcuts import redirect
from django.views.decorators.http import require_http_methods
from rest_framework import exceptions, serializers
from posthog.auth import authenticate_secondarily
from posthog.email import is_email_available
from posthog.models import Event, Team, User
from posthog.models.organization import Organization
from posthog.plugins import can_configure_plugins_via_api, can_install_plugins_via_api, reload_plugins_on_workers
from posthog.version import VERSION
class UserSerializer(serializers.ModelSerializer):
    class Meta: