Add doc for the Gitea importer

Signed-off-by: Rémy Coutable <remy@rymai.me>

doc/workflow/importing/README.md

@@ -4,6 +4,7 @@
 1. [GitHub](import_projects_from_github.md)
 1. [GitLab.com](import_projects_from_gitlab_com.md)
 1. [FogBugz](import_projects_from_fogbugz.md)
+1. [Gitea](import_projects_from_gitea.md)
 1. [SVN](migrating_from_svn.md)
 
 In addition to the specific migration documentation above, you can import any
@@ -14,4 +15,3 @@ repository is too large the import can timeout.
 
 You can copy your repos by changing the remote and pushing to the new server;
 but issues and merge requests can't be imported.
-

doc/workflow/importing/import_projects_from_gitea.md

+# Import your project from Gitea to GitLab
+
+Import your projects from Gitea to GitLab with minimal effort.
+
+## Overview
+
+>**Note:**
+As of Gitea `v1.0.0`, issue & pull-request comments cannot be imported! This is
+a [known issue][issue-401] that should be fixed in a near-future.
+
+- At its current state, Gitea importer can import:
+  - the repository description (GitLab 8.15+)
+  - the Git repository data (GitLab 8.15+)
+  - the issues (GitLab 8.15+)
+  - the pull requests (GitLab 8.15+)
+  - the milestones (GitLab 8.15+)
+  - the labels (GitLab 8.15+)
+- Repository public access is retained. If a repository is private in Gitea
+  it will be created as private in GitLab as well.
+
+## How it works
+
+Since Gitea is currently not an OAuth provider, author/assignee cannot be mapped
+to users in your GitLab's instance. This means that the project creator (most of
+the times the current user that started the import process) is set as the author,
+but a reference on the issue about the original Gitea author is kept.
+
+The importer will create any new namespaces (groups) if they don't exist or in
+the case the namespace is taken, the repository will be imported under the user's
+namespace that started the import process.
+
+## Importing your Gitea repositories
+
+The importer page is visible when you create a new project.
+
+![New project page on GitLab](img/import_projects_from_gitea_new_project_page.png)
+
+Click on the **Gitea** link and the import authorization process will start.
+
+![New Gitea project import](img/import_projects_from_gitea_new_import.png)
+
+### Authorize access to your repositories using a personal access token
+
+With this method, you will perform a one-off authorization with Gitea to grant
+GitLab access your repositories:
+
+1. Go to <https://you-gitea-instance/user/settings/applications> (replace
+   `you-gitea-instance` with the host of your Gitea instance).
+1. Click **Generate New Token**.
+1. Enter a token description.
+1. Click **Generate Token**.
+1. Copy the token hash.
+1. Go back to GitLab and provide the token to the Gitea importer.
+1. Hit the **List Your Gitea Repositories** button and wait while GitLab reads
+   your repositories' information. Once done, you'll be taken to the importer
+   page to select the repositories to import.
+
+### Select which repositories to import
+
+After you've authorized access to your Gitea repositories, you will be
+redirected to the Gitea importer page.
+
+From there, you can see the import statuses of your Gitea repositories.
+
+- Those that are being imported will show a _started_ status,
+- those already successfully imported will be green with a _done_ status,
+- whereas those that are not yet imported will have an **Import** button on the
+  right side of the table.
+
+If you want, you can import all your Gitea projects in one go by hitting
+**Import all projects** in the upper left corner.
+
+![Gitea importer page](img/import_projects_from_github_importer.png)
+
+---
+
+You can also choose a different name for the project and a different namespace,
+if you have the privileges to do so.
+
+[issue-401]: https://github.com/go-gitea/gitea/issues/401

doc/workflow/importing/import_projects_from_github.md

@@ -6,8 +6,9 @@ Import your projects from GitHub to GitLab with minimal effort.
 
 >**Note:**
 If you are an administrator you can enable the [GitHub integration][gh-import]
-in your GitLab instance sitewide. This configuration is optional, users will be
-able import their GitHub repositories with a [personal access token][gh-token].
+in your GitLab instance sitewide. This configuration is optional, users will
+still be able to import their GitHub repositories with a
+[personal access token][gh-token].
 
 - At its current state, GitHub importer can import:
   - the repository description (GitLab 7.7+)
@@ -85,7 +86,7 @@ authorization with GitHub to grant GitLab access your repositories:
 1. Click **Generate token**.
 1. Copy the token hash.
 1. Go back to GitLab and provide the token to the GitHub importer.
-1. Hit the **List your GitHub repositories** button and wait while GitLab reads
+1. Hit the **List Your GitHub Repositories** button and wait while GitLab reads
    your repositories' information. Once done, you'll be taken to the importer
    page to select the repositories to import.
 
@@ -112,7 +113,6 @@ You can also choose a different name for the project and a different namespace,
 if you have the privileges to do so.
 
 [gh-import]: ../../integration/github.md "GitHub integration"
-[new-project]: ../../gitlab-basics/create-project.md "How to create a new project in GitLab"
 [gh-integration]: #authorize-access-to-your-repositories-using-the-github-integration
 [gh-token]: #authorize-access-to-your-repositories-using-a-personal-access-token
 [social sign-in]: ../../profile/account/social_sign_in.md