Add documentation for installing snf-image-creator

docs/install.rst

 Installation
 ============
+
+This guide describes how to install snf-image-creator on an Ubuntu 12.04 LTS
+system. It it highly recommended to have virtualization capable hardware.
+snf-image-creator can work on processors that do not support virtualization but
+it will be extremely slow.
+
+Dependencies
+------------
+
+snf-image-creator depends on the following programs:
+
+ * Python 2 [http://www.python.org/]
+ * Python setuptools [http://pypi.python.org/pypi/setuptools]
+ * Python Dialog [http://pythondialog.sourceforge.net/]
+ * Python bindings for libguestfs [http://libguestfs.org/]
+ * Kamaki [https://code.grnet.gr/projects/kamaki]
+ * Python Sybprocess Wrapper [http://pypi.python.org/pypi/pbs]
+ * ANSI colors for Python [http://pypi.python.org/pypi/ansicolors]
+ * progress [http://pypi.python.org/pypi/progress]
+ * Python interface to sendfile [http://pypi.python.org/pypi/pysendfile]
+
+The first four programs (python2, setuptools, libguestfs and Python Dialog)
+need to be installed manually by the user. In an Ubuntu 12.04 LTS system this
+can be archived using packages directly provided by the distribution, using
+the following command:
+
+.. code-block:: console
+
+   $ apt-get install python-setuptools python-guestfs python-dialog
+
+The rest of the dependencies will be resolved by setuptools.
+
+Python Virtual Environment
+--------------------------
+
+Since snf-image-creator and the rest of it's dependencies won't be installed
+using packages provided by the distribution it's better to work in an isolated
+python virtual environment (virtualenv). Installing the Virtual Python
+Environment builder in Ubuntu can be accomplished using the following command:
+
+.. code-block:: console
+
+   $ apt-get install python-virtualenv
+
+Now, create a new python virtual environment like this:
+
+.. code-block:: console
+
+   $ virtualenv --system-site-packages ~/image-creator-env
+
+and activate it by executing:
+
+.. code-block:: console
+
+   $ source ~/image-creator-env/bin/activate
+
+You can later deactivate it using the following command:
+
+.. code-block:: console
+
+   $ deactivate
+
+
+kamaki Installation
+-------------------
+
+Install kamaki from source, by cloning it's repository:
+
+.. code-block:: console
+
+   $ git clone https://code.grnet.gr/git/kamaki
+   $ cd kamaki
+   $ ./setup build
+
+Then, make sure you are within the activated virtual environment before you
+execute:
+
+.. code-block:: console
+
+   $ ./setup install
+
+snf-image-creator Installation
+------------------------------
+
+Install snf-image-creator the same way:
+
+.. code-block:: console
+
+   $ git clone https://code.grnet.gr/git/snf-image-creator
+   $ cd snf-image-creator
+   $ ./setup build
+
+And from within the virtual environment execute:
+
+.. code-block:: console
+
+   $ ./setup install
+