Convert ulsPurpose from a data attribute to an languagefilter option

src/jquery.uls.core.js

@@ -54,7 +54,6 @@
 		this.$element = $( element );
 		this.options = $.extend( {}, $.fn.uls.defaults, options );
 		this.$menu = $( template );
-		this.$menu.data( 'uls-purpose', this.options.ulsPurpose );
 		this.languages = this.options.languages;
 
 		for ( code in this.languages ) {
@@ -231,6 +230,7 @@
 			this.$languageFilter.languagefilter( {
 				lcd: lcd,
 				languages: this.languages,
+				ulsPurpose: this.options.ulsPurpose,
 				searchAPI: this.options.searchAPI,
 				onSelect: $.proxy( this.select, this )
 			} );

src/jquery.uls.languagefilter.js

@@ -236,7 +236,7 @@
 				this.$element.trigger(
 					'noresults.uls',
 					query,
-					this.$element.parents( '.uls-menu' ).data( 'uls-purpose' )
+					this.options.ulsPurpose
 				);
 				return;
 			}
@@ -342,6 +342,10 @@
 		lcd: undefined,
 		// URL to which we append query parameter with the query value
 		searchAPI: undefined,
+		// What is this ULS used for.
+		// Should be set for distinguishing between different instances of ULS
+		// in the same application.
+		ulsPurpose: '',
 		// Object of language tags to language names
 		languages: [],
 		// Callback function when language is selected