improve IA of some pages

Change Description - :smile:
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### What does this change do?


* improves IA of pages: proofs#new, proofs#edit, requirements#index
* copy was improved for home#index
* dashed_name method added to convert requirement names containing dots to dashes.

**Requirements**
![screenshot 2014-04-15 18 34 30](https://cloud.githubusercontent.com/assets/331004/2713902/1e0c106e-c4ee-11e3-8821-73d73f0ee83c.png)


**Attach a new image**
![screenshot 2014-04-15 18 33 16](https://cloud.githubusercontent.com/assets/331004/2713894/07377892-c4ee-11e3-99c7-6e30ea3a7d66.png)


**Update an image**
![screenshot 2014-04-15 18 35 19](https://cloud.githubusercontent.com/assets/331004/2713916/37c4aef8-c4ee-11e3-86a9-d54ca43c623a.png)





### What testing has been done?
Tests have passed and this has been QA'd locally. Code has been reviewed as well. 

Risk Assessment
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### What are the risks? Is there a business impact?
There isn't a risk nor a business impact.