Using GLI-2.

OS: Windows 7/Vista

```
>ruby -v
ruby 1.9.3p125 (2012-02-16) [i386-mingw32]

>gem -v
1.8.24

>python -V
Python 2.7.3

>pygmentize -V
Pygments version 1.5, (c) 2006-2011 by Georg Brandl.
```

Ran `gem install docurium` (with no error) and ran `cm doc api.docurium` in the
libgit2 source tree to test it out. Output is as follows:

```
>cm doc api.docurium
C:/RailsInstaller/Ruby1.9.3/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:
36:in `require': cannot load such file -- gli (LoadError)
        from C:/RailsInstaller/Ruby1.9.3/lib/ruby/site_ruby/1.9.1/rubygems/custo
m_require.rb:36:in `require'
        from C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/docurium-0.0.5
/bin/cm:5:in `<top (required)>'
        from C:/RailsInstaller/Ruby1.9.3/bin/cm:23:in `load'
        from C:/RailsInstaller/Ruby1.9.3/bin/cm:23:in `<main>'
```

so I ran `gem install gli` (with no error) and ran `cm doc api.docurium` again.
Output is as follows:

```
>cm doc api.docurium
WARNING: Pygments not found. Using webservice.
You should include GLI::App instead
GLI.run no longer works for GLI-2, you must just call `run(ARGV)' instead
either fix your app, or use the latest GLI in the 1.x family
```

Obviously I do have pygments installed so I thought it might be complaining
about not having pygments.rb, so I ran `gem install pygments.rb` and ran
`cm doc api.docurium`. The output remained the same.

Hopefully this PR will eventually get it working again (for me at least).