Optional V3 Web Search and support for search SLURLs

Added "Use web-based search instead of legacy v1 search" checkbox to System->General preferences

Unified all functions to display search floater into toggle_search_floater and LLFloaterSearch::showInstance
Added UseWebSearch and UseWebSearchSLURL debug settings for flexible configurations
- SLURLs with legacy search cannot always present the same results as web
Added SearchURL debug setting, a separate setting from the one used in the all tab, slightly different and always set by response["search"] on OSGrid logins to detect if websearch is supported
Cleaned up llfloaterdirectory includes and added "Search.WebFloater" to the CommitCallbackRegistrar in case we ever want to add a button or something to open web search (couldn't find a nice place for it, sadly), also added more functions to show specific tabs and performQueryOn to search a tab with specific query on LLPanelDirBrowser's

indra/newview/llstatusbar.cpp

@@ -41,12 +41,12 @@
 #include "llenvmanager.h"
 #include "llfloaterbuycurrency.h"
 #include "llfloaterchat.h"
-#include "llfloaterdirectory.h"		// to spawn search
 #include "llfloaterinventory.h"
 #include "llfloaterlagmeter.h"
 #include "llfloaterland.h"
 #include "llfloaterregioninfo.h"
 #include "llfloaterscriptdebug.h"
+#include "llfloatersearch.h"
 #include "llhudicon.h"
 #include "llkeyboard.h"
 #include "lllineeditor.h"
@@ -994,8 +994,9 @@ void LLStatusBar::onCommitSearch(LLUICtrl*, void* data)
 void LLStatusBar::onClickSearch(void* data)
 {
 	LLStatusBar* self = (LLStatusBar*)data;
-	std::string search_text = self->childGetText("search_editor");
-	LLFloaterDirectory::showFindAll(search_text);
+	LLFloaterSearch::SearchQuery search;
+	search.query = self->childGetText("search_editor");
+	LLFloaterSearch::showInstance(search);
 }
 
 // static