Added JSON API for creating dropdown lists
Incorporated drop down select control for data themes

This hooks up the client side data them selection control to the
server side querying, including the criteria display.
Incorporated drop down select control for sub themes
Incorporated drop down control for parameter selection
Incorporated drop down control for data holder selection
Incorporated drop down control for access type selection
Incorporated drop down control for data format selection
Return no parameters if there are no data theme or sub-theme ids

Otherwise an interminable and pointless SQL statement is issued.
Improve portability of client side javascript
Fix the Query deepcopy operation to include the vocabs and db
Fix association of parameters with data themes and sub themes

Parameters are now associated with data themes and sub themes using
*both* `narrower` and `related` concepts rather than just the former
as was previously the case.
Made the theme dropdowns capable of multiple selection
 Made the advanced dropdowns capable of multiple selection
Fixed formatting bug in criteria summary
Fixed IE 8 bug in new dropdown functionality
Fixed display problem in theme dropdowns with only one entry
Replaced jQuery multiselect with Chosen for the dropdowns
Simplified the search help text
Fix the quoting of parameter strings

This is as per instructions in an email from Steve Donegan on Thu, 9
May 2013 13:50:31
Move theme search dropdowns to the Advanced Search section