Long line wrapping (rebased onto dev_5_0)


This is the same as gh-3026 but rebased onto dev_5_0.

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It looks like that long lines in the description where there are only letters and underline chars are unwrapped.
![firefoxscreensnapz004](https://cloud.githubusercontent.com/assets/1065155/4232538/2a36b7c0-399e-11e4-838d-fb1ee21af434.png)

Testing on all possible web browsers: IE, FF, Safari, Opera, including mobile devices, tablets, etc.

To test please try to paste the following text in the description and see if is wrapped.
```
This_is_a_very_long_text_that_should_break_on_any_letter_This_is_a_very_long_text_that_should_break_on_any_letter_This_is_a_very_long_text_that_should_break_on_any_letter_This_is_a_very_long_text_that_should_break_on_any_letter_
```
![firefoxscreensnapz003](https://cloud.githubusercontent.com/assets/1065155/4232523/f9991298-399d-11e4-8072-db8d9144ef98.png)