Bug fixes and interface improvements -- see the comments in individual c...

- "Variant 0" in sample code now correctly marked as "Variant 1"
- p value in report changed to confidence percentile, which is easier to understand. p value can be added back in, in a less obtrusive way for those who really want it
- Sample Code boxes are now a consistent width, which looks a little nicer
- Cached transient is deleted when an experiment is set to active... still doesn't work though, needs tweaking
- Bypassing language pack for Variant Shortcode plugin, since it caused TinyMCE not to load