ENYO-365: Prevent text from overflowing bounds.

### Issue
When explicit dimensions are set for an `enyo.RichText` control, text can overflow the bounds of the control.

### Fix
We set `overflow:hidden` for this control and apply `word-wrap:break-word` to have consistent line-breaking behavior among browsers.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>