Add missing white space

On the welcome page a white space is missing between `our` and `templates`, as below:
![sharelatex-before](https://cloud.githubusercontent.com/assets/5656196/4111847/a1f42c02-3214-11e4-98fb-282f59db7307.png)

after fix:
![sharelatex-after](https://cloud.githubusercontent.com/assets/5656196/4111846/a1f016bc-3214-11e4-9f58-ed3f34ec4e8d.png)