Fix admin element validation (plugin manager):

(In code change sequence:)
1. Add JS Hint settings.
2. Allow all accordions to be closed (more user friendly).
3. Fix spelling iniAccordian -> iniAccordion.
4. Slightly more responsive page load (check for all ajax loads more frequently).
5. On load only open first plugin accordion if 1 plugin.
6. Fix bug which showed second accordion rather than first i.e. display(1) should be display(0).
7. Show "Please select" as accordion heading when plugin has not yet been selected (rather than blank).
8. HTML improvements - ajax code is loaded insite accordion-body rather than after it  - looks slightly better. 
9. Add debugging console messages.
10. Use fconsole rather than console.log for ajax errors.
11. Nicer ajax error messages and speeling mistook korrekted.
12.  Renaming of ids, names and fors now comprehensively handled on plugin delete.
13. Faster animation to make it more responsive.
14. Accordion heading show "loading..." during ajax.