Use Kirby's Toolkit for handling session variables.
Nest breakpoint inlcude.

Now works correctly with Libsass 3.
Updte and cleanup plugins.
Use new Kirby 2 field method for kirbytext(), html(), etc.

E.g. use `$page->text()->kirbytext()` instead of the old `kirbytext($page->text())`.
Add field method for smartypants via plugin.

Smartypants field method: `$page->title()->smartypants()`.
Add field method to titlecase plugin.

Titlecase field method: `$page->title()->smartypants()->titlecase()`.
Add Sass pagination module.