Remove unnecessary navigation bar to access mobile site and Re-add flash warning to registrations mobile  - Only develop branch

# Before

![Pantallazo_](https://f.cloud.github.com/assets/1108789/320959/2d8a2a4e-997f-11e2-8769-c7b543b8afa8.png)

# After

![Pantallazo-1](https://f.cloud.github.com/assets/1108789/320961/339203bc-997f-11e2-8af0-79a3d13a88c0.png)

And Remove excess `:css` 

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# Before

![01](https://f.cloud.github.com/assets/1108789/321037/651edb14-9987-11e2-9638-32f3a01dd18d.png)

![02](https://f.cloud.github.com/assets/1108789/321045/e1003a52-9987-11e2-83ef-8bfc1f91a4fd.png)

# After

![03](https://f.cloud.github.com/assets/1108789/321041/9d3619cc-9987-11e2-82eb-9f66d8bf586f.png)

![04](https://f.cloud.github.com/assets/1108789/321042/a35f5ef8-9987-11e2-917b-014b8c9047af.png)

And Remove excess `:css`