Changed 'Send to DPaste' link (from [6820]) on debug page to wording that's...

Changed 'Send to DPaste' link (from [6820]) on debug page to wording that's much less inside-basebally. Also changed it so that the button only shows up after clicking 'Switch to copy-and-paste view', so people know what they're getting into. Also unconverted some XHTML tags, as the page uses an HTML 4.01 doctype.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6882 bcc190cf-cafb-0310-a4f2-bffc1f526a37