Add in-place-edit to about/feature pages.

Closes #205 

This also adds a title field in the 'Add new page' button.

This PR does not add edit in place for the title of the home page (since that would require moving that into the form).  I'll create another ticket for that.

### New button
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![screen shot 2014-02-25 at 7 39 51 pm](https://f.cloud.github.com/assets/96776/2266527/848759c6-9e9b-11e3-8696-28f8980ebee0.png)

### Title field in on button hover
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![screen shot 2014-02-25 at 5 58 42 pm](https://f.cloud.github.com/assets/96776/2266528/927333b6-9e9b-11e3-9a35-5bac62141498.png)

### New page added
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![screen shot 2014-02-25 at 6 01 21 pm](https://f.cloud.github.com/assets/96776/2266537/b3ddd218-9e9b-11e3-94d4-0fae046dafaf.png)


### Page title edit-in-place
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![screen shot 2014-02-25 at 5 58 56 pm](https://f.cloud.github.com/assets/96776/2266540/bfc3cde4-9e9b-11e3-8dc5-a330ec6f4a24.png)