Navigation change soulmates to dating

According to tests people like 'dating' more than 'soulmates'. We will be still tracking it as 'soulmates'.

Before:
![screen shot 2014-12-08 at 15 38 36](https://cloud.githubusercontent.com/assets/2579465/5341820/02da2f2a-7ef1-11e4-806f-24211ff538aa.png)

After:
![screen shot 2014-12-08 at 15 38 07](https://cloud.githubusercontent.com/assets/2579465/5341829/0b0b6510-7ef1-11e4-90f3-4bc698683177.png)