feat: Login via CLI (#298)

Fixes #210 - this isPR implements `coder login` in the case where the default user is already created.

This change adds:
- A prompt in the case where there is not an initial user that opens the server URL + requests a session token
  - This ports over some code from v1 for the `openURL` and `isWSL` functions to support opening the browser
- A `/api/v2/api-keys` endpoint that can be `POST`'d to in order to request a new api key for a user
  - This route was inspired by the v1 functionality
- A `cli-auth` route + page that shows the generated api key
- Tests for the new code + storybook for the new UI

The `/cli-auth` route, like in v1, is very minimal:

<img width="624" alt="Screen Shot 2022-02-16 at 5 05 07 PM" src="https://user-images.githubusercontent.com/88213859/154384627-78ab9841-27bf-490f-9bbe-23f8173c9e97.png">

And the terminal UX looks like this:

![2022-02-16 17 13 29](https://user-images.githubusercontent.com/88213859/154385225-509c78d7-840c-4cab-8f1e-074fede8f97e.gif)

coderd/users_test.go

@@ -119,6 +119,33 @@ func TestOrganizationsByUser(t *testing.T) {
 	require.Len(t, orgs, 1)
 }
 
+func TestPostKey(t *testing.T) {
+	t.Parallel()
+	t.Run("InvalidUser", func(t *testing.T) {
+		t.Parallel()
+		client := coderdtest.New(t)
+		_ = coderdtest.CreateInitialUser(t, client)
+
+		// Clear session token
+		client.SessionToken = ""
+		// ...and request an API key
+		_, err := client.CreateAPIKey(context.Background())
+		var apiErr *codersdk.Error
+		require.ErrorAs(t, err, &apiErr)
+		require.Equal(t, http.StatusUnauthorized, apiErr.StatusCode())
+	})
+
+	t.Run("Success", func(t *testing.T) {
+		t.Parallel()
+		client := coderdtest.New(t)
+		_ = coderdtest.CreateInitialUser(t, client)
+		apiKey, err := client.CreateAPIKey(context.Background())
+		require.NotNil(t, apiKey)
+		require.GreaterOrEqual(t, len(apiKey.Key), 2)
+		require.NoError(t, err)
+	})
+}
+
 func TestPostLogin(t *testing.T) {
 	t.Parallel()
 	t.Run("InvalidUser", func(t *testing.T) {