[IMP] layout proposals

[gjotten]

Am proposing to implement below changes:

• Added alternating even-row stripe
  Visual aid for scanning rows which replaces cell borders for a cleaner look
• Header background changed
  To match even-row stripe color for visual consistency
• Popup width made narrower
  Chrome popup windows seems to be capped; the old value caused content to overflow; also adjusted column widths
• **Split html from body overflow rule **
• Both shared overflow-y: auto, producing AFAICS a double vertical scrollbar
• Removed .table-scroll overflow
  Second scroll container causing the same double scrollbar
• Row backgrounds target > td instead of tr
  tr background doesn't reliably show through td cells
• Dead action column width rule
  The first-child rule was overriding .action-col, making it not fire

See attached file, please review and implement if acceptable.

popup.css