Also fix some unicode issues

Remove the buggy conversion of metadata to strings

Encode it to UTF-8 before feeding it to kamaki, otherwise kamaki may
fail.

* Use absolute path when opening README.md
* Fix a pep8 issue

Prior to this patch, the use_persistent_block_device_names sysprep would
trigger a exception if applied on CoreOS Linux because of the lack of
/etc/fstab.

Keep track of the cloud accounts an image was uploaded and registered
on. When changing the current cloud account, the registration info
should also change to represent the current cloud's status. We may have
registered an image on an account and then switch to a different
account. The image should not be shown as registered, unless we switch
back to the old one.

If extlinux is installed on the root partition (the OS does not have a
separate /boot partition) it needs to be reinstalled, otherwise the OS
won't boot.

Detect if a partition has a bootloader installed on its Volume Boot
Record.

Detect the bootloader that is installed on the MBR and assign it to
the BOOTSTRAP image property.

There were cases where the parameter was of type long and this raises
exceptions in newer versions of the python-dialog.

We were not using it.

The method was hot-patched into the pythondialog library if it was
missing. Use the same format found in pythondialog 3.x

New versions of python-dialog will create deprecation warnings when
using the old values

Use dialog constants to compare with the return value of yesno(). In
newer versions of the dialog library, the return value of the function
is unicode strings.

 * Add text/plain as content type in the md5sum file
 * Add application/json as content type in the meta file

Allow the user to upload the image to a different container than the
"images" one.

As the documentation of libguestfs states, a separated thread should
be started after mount_local has finished and before mount_local_run,
which is a blocking command, gets started. Till now, we used to start
the thread just before mount_local.

Also change the mount() method to be able to use it standalone without
a with statement.

Export the image metadata as environment variables before running
scripts on the mounted image. This way the metadata will be visible
and can be used by the scripts if needed.

Allow the user to change the destination container when uploading
images.

This option can be used to prefix each output line with a timestamp.

If the user specifies /dev/null as output file, omit dumping the image.
This can be used for debug reasons.

Update the image properties accordingly if this is the case

Bump version to 0.9next

Increase the default boot and the shutdown timeout in windows to 10 and
5 minutes respectfully.

Prior to this, if you tried to install the same version of the VirtIO
drivers that where already installed on a Windows media, you would end
up just uninstalling the old ones. This happened because
snf-image-creator added code for installing the new drivers and then for
removing the old ones. Windows would ignore the first request, since the
drivers were already present in the database, but would perform the
second one.

This fixes #44

Fix a typo that raised an AttributeError exception when the input media
was a *BSD system.

Also update the year in the "Copyright" section