Make it clear that we need to enable omniauth for SAML and Bitbucket

doc/integration/bitbucket.md

 # Integrate your GitLab server with Bitbucket
 
+NOTE: **Note:**
+You need to [enable OmniAuth](omniauth.md) in order to use this.
+
 Import projects from Bitbucket.org and login to your GitLab instance with your
 Bitbucket.org account.
 
@@ -76,13 +79,13 @@ you to use.
     sudo -u git -H editor /home/git/gitlab/config/gitlab.yml
     ```
 
-1.  Follow the [Initial OmniAuth Configuration](omniauth.md#initial-omniauth-configuration)
-    for initial settings.
 1.  Add the Bitbucket provider configuration:
 
     For Omnibus packages:
 
     ```ruby
+    gitlab_rails['omniauth_enabled'] = true
+
     gitlab_rails['omniauth_providers'] = [
       {
         "name" => "bitbucket",
@@ -96,6 +99,9 @@ you to use.
     For installations from source:
 
     ```yaml
+    omniauth:
+      enabled: true
+      providers:
         - { name: 'bitbucket',
             app_id: 'BITBUCKET_APP_KEY',
             app_secret: 'BITBUCKET_APP_SECRET',
@@ -121,6 +127,9 @@ well, the user will be returned to GitLab and will be signed in.
 Once the above configuration is set up, you can use Bitbucket to sign into
 GitLab and [start importing your projects][bb-import].
 
+If you don't want to enable signing in with Bitbucket but just want to import
+projects from Bitbucket, you could [disable it in the admin panel](omniauth.md#enable-or-disable-sign-in-with-an-omniauth-provider-without-disabling-import-sources).
+
 [init-oauth]: omniauth.md#initial-omniauth-configuration
 [bb-import]: ../workflow/importing/import_projects_from_bitbucket.md
 [bb-old]: https://gitlab.com/gitlab-org/gitlab-ce/blob/8-14-stable/doc/integration/bitbucket.md

doc/integration/saml.md

 # SAML OmniAuth Provider
 
+NOTE: **Note:**
+You need to [enable OmniAuth](omniauth.md) in order to use this.
+
 GitLab can be configured to act as a SAML 2.0 Service Provider (SP). This allows
 GitLab to consume assertions from a SAML 2.0 Identity Provider (IdP) such as
 Microsoft ADFS to authenticate users.
@@ -26,15 +29,13 @@ in your SAML IdP:
     sudo -u git -H editor config/gitlab.yml
     ```
 
-1.  See [Initial OmniAuth Configuration](omniauth.md#initial-omniauth-configuration)
-    for initial settings.
-
 1.  To allow your users to use SAML to sign up without having to manually create
     an account first, don't forget to add the following values to your configuration:
 
     For omnibus package:
 
     ```ruby
+    gitlab_rails['omniauth_enabled'] = true
     gitlab_rails['omniauth_allow_single_sign_on'] = ['saml']
     gitlab_rails['omniauth_block_auto_created_users'] = false
     ```
@@ -42,6 +43,8 @@ in your SAML IdP:
     For installations from source:
 
     ```yaml
+    omniauth:
+      enabled: true
       allow_single_sign_on: ["saml"]
       block_auto_created_users: false
     ```
@@ -84,6 +87,8 @@ in your SAML IdP:
     For installations from source:
 
     ```yaml
+    omniauth:
+      providers:
         - {
             name: 'saml',
             args: {
@@ -220,6 +225,8 @@ If you want some SAML authentication methods to count as 2FA on a per session ba
 1. Edit `config/gitlab.yml`:
 
     ```yaml
+    omniauth:
+      providers:
         - {
             name: 'saml',
             args: {
@@ -234,7 +241,6 @@ If you want some SAML authentication methods to count as 2FA on a per session ba
                         'urn:oasis:names:tc:SAML:2.0:ac:classes:SecondFactorOTPSMS',
                         'urn:oasis:names:tc:SAML:2.0:ac:classes:SecondFactorIGTOKEN'
                       ]
-    
                   },
             label: 'Company Login' # optional label for SAML login button, defaults to "Saml"
           }
@@ -247,11 +253,11 @@ In addition to the changes in GitLab, make sure that your Idp is returning the
 `AuthnContext`. For example:
 
 ```xml
-    <saml:AuthnStatement> 
+<saml:AuthnStatement>
     <saml:AuthnContext>
         <saml:AuthnContextClassRef>urn:oasis:names:tc:SAML:2.0:ac:classes:MediumStrongCertificateProtectedTransport</saml:AuthnContextClassRef>
     </saml:AuthnContext>
-    </saml:AuthnStatement>
+</saml:AuthnStatement>
 ```
 
 ## Customization