Add missing require 'pathname'

I'm getting the following backtrace without it

```
/opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/fog-octocloud-0.5.0/lib/fog/octocloud/compute.rb:81:in `initialize': unin
itialized constant Fog::Compute::Octocloud::Real::Pathname (NameError)
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/fog-1.14.0/lib/fog/core/service.rb:68:in `new'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/fog-1.14.0/lib/fog/core/service.rb:68:in `new'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/fog-octocloud-0.5.0/lib/fog/octocloud.rb:24:in `new'
        from test.rb:6:in `<main>'
```

Test code:

```ruby
require 'pp'
require 'fog'
require 'fog-octocloud'

octoc = Fog::Compute.new({
  :provider => 'octocloud',
  :octocloud_api_key => 'redacted',
  :octocloud_url => 'redacted'
})

pp octoc.servers
```
Added basic getting started doku-fu, handcrafted with <3
Merge pull request #8 from rubiojr/require-pathname

Add missing require 'pathname'
Minor tweaks to the Getting Started guide

Added @lstoll suggestions.
Warn if we can't load credentials from ~/.fog instead of raising

This will allow us to use the local (Fusion) driver:

```ruby
require 'fog'
require 'fog-octocloud'

octoc = Fog::Compute.new( :provider => 'octocloud' )
```

See #10
Merge pull request #9 from rubiojr/basic-docs

Added basic getting started doku-fu, handcrafted with <3
Merge pull request #11 from rubiojr/issue-10

Warn if we can't load credentials from ~/.fog instead of raising
Minor fix to be able import local OVA files

OVA -> cube conversion is not working for me for some reason.

The patch changes the convert_cube.rb request so that when converting
the OVA to a Cube, all the cube files remain in the same directory
(named after the cube name).

Right now (without the patch), the conversion process produces:

```sh
$ find ~/.octocloud/boxes/
/Users/rubiojr/.octocloud/boxes/
/Users/rubiojr/.octocloud/boxes//test-cube
/Users/rubiojr/.octocloud/boxes//test-cube/.md5
/Users/rubiojr/.octocloud/boxes//test-cube.vmwarevm
/Users/rubiojr/.octocloud/boxes//test-cube.vmwarevm/vmwarebox-disk1.vmdk
/Users/rubiojr/.octocloud/boxes//test-cube.vmwarevm/vmwarebox.vmx
```

So the .md5 is created in a different directory (test-cube). This
apparently breaks cube listings at least.

The code I'm using to test:

```ruby
require 'pp'
require 'fog'
require 'fog-octocloud'

octoc = Fog::Compute.new( :provider => 'octocloud' )
cube = octoc.cubes.create :name => 'test-cube',
                          :source => File.expand_path('~/tmp/tinycore-477.ova')

pp octoc.cubes
```

This raises an exception when listing the cubes after
importing/converting the OVA to a Cube:

```sh
/Users/rubiojr/tmp/fog-octocloud/lib/fog/octocloud/requests/compute/local_list_boxes.rb:12:in `initialize': No such file or directory - /Users/rubiojr/.octocloud/boxes/test-cube.vmwarevm/.md5 (Errno::ENOENT)
        from /Users/rubiojr/tmp/fog-octocloud/lib/fog/octocloud/requests/compute/local_list_boxes.rb:12:in `open'
        from /Users/rubiojr/tmp/fog-octocloud/lib/fog/octocloud/requests/compute/local_list_boxes.rb:12:in `block in local_list_boxes'
        from /Users/rubiojr/tmp/fog-octocloud/lib/fog/octocloud/requests/compute/local_list_boxes.rb:9:in `map'
        from /Users/rubiojr/tmp/fog-octocloud/lib/fog/octocloud/requests/compute/local_list_boxes.rb:9:in `local_list_boxes'
        from /Users/rubiojr/tmp/fog-octocloud/lib/fog/octocloud/models/compute/cubes.rb:14:in `all'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/fog-1.14.0/lib/fog/core/collection.rb:141:in `lazy_load'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/gems/1.9.1/gems/fog-1.14.0/lib/fog/core/collection.rb:22:in `pretty_print'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:154:in `block in pp'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/prettyprint.rb:217:in `block (2 levels) in group'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/prettyprint.rb:243:in `nest'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/prettyprint.rb:216:in `block in group'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/prettyprint.rb:228:in `group_sub'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/prettyprint.rb:215:in `group'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:154:in `pp'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:77:in `block in pp'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:121:in `guard_inspect_key'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:77:in `pp'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:60:in `block in pp'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:59:in `each'
        from /opt/boxen/rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/pp.rb:59:in `pp'
        from test2.rb:18:in `<main>'
```

With the patch applied, the <cube-name>.vmwarevm directory is renamed to
<cube-name> and the .md5 is created inside of it.

I'm not really sure if this is the behaviour we should expect so any input on
this is greatly appreciated.
Added getting started docs for the VMware Fusion driver
Added local_import_box request tests

- Test OVA import
- Added a test helper to download a fully functional OVA for testing.
Test also remote (URL) OVA import
Skip local_import_box tests when running under Travis CI
Updated test OVA URL

Moved the Tiny Core test OVA to S3
Merge pull request #12 from rubiojr/fusion-ova-import-fixes

Minor fix to be able import local OVA files
Merge pull request #13 from rubiojr/fusion-driver-docs

Added getting started docs for the VMware Fusion driver