Fix for Brakeman warnings

Brakeman complains with:

+Errors+
+-----------------------------------+----------------------------------------->>
| Error                             | Location                                >>
+-----------------------------------+----------------------------------------->>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xC2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
| Invalid US-ASCII character "\xE2" | While compiling HAML in /Users/civilclai>>
+-----------------------------------+----------------------------------------->>

This commit is there to set the language environment.
Merge pull request #229 from ministryofjustice/brakeman-lang-var

Fix for Brakeman warnings