Fix problem when using base HTML tag

This fixes a problem when your html document uses the [HTML base tag](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/base). If you are in the first or last page and you click the "&laquo; previous" or "next &raquo;" link, respectively, you will be redirected to the main page of your site.

Steps to reproduce:

#### 1.- Add HTML base tag to your layout
```html
<!DOCTYPE html>
<html>
	<head>
		...
		<base href="..." />
		...
	</head>
	<body>
		...
	</body>
</html>
```
#### 2.- Click Previous or Next link in one of the edges of the pagination

Visit the first page and click the pagination previous (&laquo;) link or visit the last page and click the next (&raquo;) link.

You will be sent to the home page of your site.

----
IMHO makes no sense to show the the previous (&laquo;) link when you are in the first page (or same for the next &raquo; link and the last page) but I understand this is just my personal taste so I decided to keep them in the PR.