OC5 beta 2 - prevent multiple slashes in a row when building URLs.

When you hover over e.g. a file name with your cursor you can see that the generated URL contains multiple slashes in a row:

![20130227_owncloud_three_slashes_in_a_row](https://f.cloud.github.com/assets/2572764/202167/49a6decc-8109-11e2-9694-8d9040791024.png)