Added tutorial about initializing a repository.

Additionally, for this and future examples, there is a test_doc.py
suite to contain all code mentioned in the docs. That way, we know
if things stop working.

Fixes #236

Author: Byron

doc/source/tutorial.rst

@@ -415,6 +415,22 @@ The previous approach would brutally overwrite the user's changes in the working
 	repo.heads.master.checkout()			# checkout the branch using git-checkout
 	repo.heads.other_branch.checkout()
 
+Initializing a repository
+*************************
+
+In this example, we will initialize an empty repository, add an empty file to the index, and commit the change::
+
+    repo_dir = 'my-new-repo'
+    file_name = os.path.join(repo_dir, 'new-file')
+
+    r = git.Repo.init(repo_dir)
+    # This function just creates an empty file ... 
+    touch(file_name)
+    r.index.add([file_name])
+    r.index.commit("initial commit")
+
+Please have a look at the individual methods as they usually support a vast amount of arguments to customize their behavior.
+
 Using git directly
 ******************
 In case you are missing functionality as it has not been wrapped, you may conveniently use the git command directly. It is owned by each repository instance::

git/test/test_docs.py

@@ -0,0 +1,26 @@
+#-*-coding:utf-8-*-
+# test_git.py
+# Copyright (C) 2008, 2009 Michael Trier (mtrier@gmail.com) and contributors
+#
+# This module is part of GitPython and is released under
+# the BSD License: http://www.opensource.org/licenses/bsd-license.php
+import os
+
+import git
+from git.test.lib import TestBase
+from gitdb.test.lib import with_rw_directory
+from git.repo.fun import touch
+
+
+class TestGit(TestBase):
+
+    @with_rw_directory
+    def test_add_file_and_commit(self, rw_dir):
+        repo_dir = os.path.join(rw_dir, 'my-new-repo')
+        file_name = os.path.join(repo_dir, 'new-file')
+
+        r = git.Repo.init(repo_dir)
+        # This function just creates an empty file ...
+        touch(file_name)
+        r.index.add([file_name])
+        r.index.commit("initial commit")