[gnome-builder] doc: update installation docs with more description

[Christian Hergert <chergert src gnome org>]

commit 379363b8744dce6929ec33ef6ec62e5cc4efc0d7
Author: Christian Hergert <chergert redhat com>
Date:   Wed Mar 1 01:42:43 2017 -0800

    doc: update installation docs with more description
    
    We really want people to read the Newcomers docs before having them run
    the commands below. They are really just for guidance.

 doc/installation.rst |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/doc/installation.rst b/doc/installation.rst
index 04a6c02..48aec73 100644
--- a/doc/installation.rst
+++ b/doc/installation.rst
@@ -60,6 +60,8 @@ We are aggressively moving towards using Flatpak for contributing to Builder, bu
 Command Line
 ^^^^^^^^^^^^
 
+.. note:: You almost certainly want to read the `Newcomers Tutorial`_ on how to build a GNOME application 
before proceeding.
+
 .. code-block:: sh
 
    $ git clone git://git.gnome.org/jhbuild.git
@@ -71,7 +73,7 @@ Command Line
    $ jhbuild build gnome-builder
    $ jhbuild run gnome-builder
 
-.. warning:: Do not install JHBuild via your Linux distribution's package manager. It will be out of date.
+.. warning:: While it may be tempting to install jhbuild using your Linux distribution's package manager, it 
will lack an updated description of the GNOME modules and is therefore insufficient. Always install jhbuild 
from git.
 
 
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