add popover for menus

- repurpose help popover for menu popover
- add directive to pid selector (only visible if isMetrics flag is true)
- remove duplicate style
- remove watchdog
- add flag to hide on page click
- otherwise use mouseenter/mouseleave to hide menu
- add global pageClick event
Merge pull request #592 from strongloop/feature/cog-drop-down

add popover for menus

- repurpose help popover for menu popover
- add directive to pid selector (only visible if isMetrics flag is true)
- remove duplicate style
- remove watchdog
- add flag to hide on page click
- otherwise use mouseenter/mouseleave to hide menu
- add global pageClick event

#580