Update installation method

In the "Installation from source" scenario, add python-sendfile to the
list of dependecies that will be installed via apt-get. Else, it would
complain about missing C headers and the user would need to download
python-dev instead.

docs/install.rst

@@ -3,8 +3,7 @@ Installation
 
 This guide describes how to install snf-image-creator on your machine. It is
 highly recommended to have virtualization capable hardware. snf-image-creator
-will work on processors that do not support virtualization but it will be
-extremely slow.
+will work on processors that do not support virtualization but it will be slow.
 
 Dependencies
 ============
@@ -15,11 +14,11 @@ snf-image-creator depends on the following programs:
  * Python setuptools [http://pypi.python.org/pypi/setuptools]
  * Python Dialog [http://pythondialog.sourceforge.net/]
  * Python bindings for libguestfs [http://libguestfs.org/]
+ * Python interface to sendfile [http://pypi.python.org/pypi/pysendfile]
  * Kamaki [https://code.grnet.gr/projects/kamaki]
  * Python sh (previously pbs) [https://github.com/amoffat/sh]
  * 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 above dependencies are resolved differently, depending on the installation
 method you choose. There are two installation methods available:
@@ -84,7 +83,7 @@ snf-image-creator, along with its dependencies, with the following command:
 
    $ sudo apt-get install snf-image-creator
 
-The installation might take a while. Please note that at some point during the
+The installation may take a while. Please note that at some point during the
 installation you will be prompted to create/update a "supermin appliance". This
 is a setting regarding libguestfs and you can safely choose "Yes".
 
@@ -95,14 +94,14 @@ This method provides you with the cutting edge of snf-image-creator, which
 gives you access to all the latest features. Keep in mind, however,
 that you may experience instability issues.
 
-The first four dependencies (python2, setuptools, Python-Dialog, and
-libguestfs) need to be installed manually by the user. In an Ubuntu 12.04 LTS
-system this can be achieved by installing packages provided by the
+The first five dependencies (python2, setuptools, Python-Dialog, libguestfs and
+python-sendfile) need to be installed manually by the user. In an Ubuntu 12.04
+LTS system this can be achieved by installing packages provided by the
 distribution, using the following command:
 
 .. code-block:: console
 
-   $ apt-get install python-setuptools python-guestfs python-dialog
+   $ apt-get install python-setuptools python-guestfs python-dialog python-sendfile
 
 The rest of the dependencies will be automatically resolved by setuptools.
 Note that at some point during the installation, you will be prompted to
@@ -193,8 +192,8 @@ Install snf-image-creator the same way:
 
    $ cd ~
    $ git clone https://code.grnet.gr/git/snf-image-creator
-   $ git checkout stable-0.1
    $ cd snf-image-creator
+   $ git checkout stable-0.1
    $ ./setup.py build
 
 And from within the virtual environment execute:

docs/usage.rst

@@ -211,7 +211,7 @@ Verify that it has been downloaded correctly:
    $ echo 'a8c667e871f48f3a662f3fbf1c3ddb17  ubuntu-12.04.1-server-amd64.iso' > check.md5
    $ md5sum -c check.md5
 
-Create a 2G sparce file to host the new system:
+Create a 2G sparse file to host the new system:
 
 .. code-block:: console