Add the ability to link static elements in the nav

[mateimicu]

Basically you can define something like this

[[params.static]]                                                                                                                                                                                            
title = "Slides"
url = "http://slides.mateimicu.com"

and it will show up like this:

And of course you can add multiple links:

[[params.static]]                                                                                                                                                                                            
title = "Slides"
url = "http://slides.mateimicu.com"
[[params.static]]                                                                                                                                                                                            
title = "Slides2"
url = "http://slides.mateimicu.com/2"

[ribice]

Can you document these changes in Readme? Thanks!

[mateimicu]

Added a little section with a config sample.
Would you like me to add a picture ?

[ribice]

Not needed. I'll probably edit the text a bit tomorrow, and add it to example site as well.

[russparsloe]

This seems similar to sections (#23) which uses this configuration format:

[params.sections]
  "/about" = "About"
  "/posts" = "Posts"

Can this be altered to make both options consistent in how they are configured in config.toml?

[ribice]

@russparsloe That would be great!

[mateimicu]

I'll make the change today :D

[ribice]

@mateimicu: Any update?

[mateimicu]

Updated the PR