[gnome-builder] doc: Explain how to build the Builder flatpak locally

[Matthew Leeds <mwleeds src gnome org>]

commit a90f7d1743cce71c35bda1512840addc077e5fca
Author: Matthew Leeds <mleeds redhat com>
Date:   Wed Mar 22 11:47:21 2017 -0500

    doc: Explain how to build the Builder flatpak locally

 doc/installation.rst |   21 +++++++++++++++++++++
 1 files changed, 21 insertions(+), 0 deletions(-)
---
diff --git a/doc/installation.rst b/doc/installation.rst
index 9da0b6b..32202b9 100644
--- a/doc/installation.rst
+++ b/doc/installation.rst
@@ -50,6 +50,27 @@ You can also use the command line to install Builder:
 
 .. note:: Nightly builds are built with tracing enabled. The tracing is fairly lightweight, but it includes 
a great deal of more debugging information.
 
+Local Flatpak Builds
+--------------------
+
+You can also build Builder as a flatpak yourself to test local changes. First, make a repo for your local 
builds:
+
+.. code-block:: sh
+
+   $ mkdir ~/my-flatpak-builds
+   $ flatpak remote-add --user --no-gpg-verify my-flatpak-builds ~/my-flatpak-builds
+
+Now, in Builder's source directory, use ``flatpak-builder`` to build a Builder flatpak and install it
+
+.. code-block:: sh
+
+   $ git clone https://git.gnome.org/browse/gnome-builder/
+   $ cd gnome-builder
+   $ mkdir app
+   $ flatpak-builder --ccache --repo=$HOME/my-flatpak-builds app org.gnome.Builder.json
+   $ flatpak install --user my-flatpak-builds org.gnome.Builder
+
+.. note:: After following these steps once you can omit adding the remote or creating the app directory. 
You'll also need to add the ``--force-clean`` option to flatpak-builder and use ``flatpak update`` rather 
than ``flatpak install``.
 
 .. _via-jhbuild: