Password partials updated to spanish

Password partials were updated to spanish && switched to slim template engine
this was my first commit :+1: 

 
![screen shot 2014-09-03 at 23 15 24](https://cloud.githubusercontent.com/assets/1057021/4144869/2525c3e8-33ea-11e4-9b1e-21ccfacc5c45.png)

## TODO:
- [x] changed text on forgot password screen
- [ ] create cucumber test
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